The slate is full this week as we come back for our first post-All-Star Break edition of Coach Spins’ Clipboard. From some key play over the last 15 games to musings on defensive statistics after the Sloan Conference, we dabble in every type of topic this week.

Let’s get right to it:

1. A Polarizing Relationship: Defensive Impact and Statistical Analysis

During my numerous travels these past few weeks, I’ve been able to load up on NBA podcasts and hear some great insights from other minds surrounding the league. One of the many topics to pique my interest was the thought of finding value in defensive metrics for individuals. At this point, we have a lot of measures for team impact and effectiveness on both ends of the court. Individual offensive metrics, dictated mainly by scoring and assist-to-turnover impact, provides a decent picture of how many players in the league help or hinder their club.

I’ve long struggled with how to quantify a player’s defensive impact, as well as how to articulate the theoretical flaws in any statistic designed to do so. Did you know that since joining the Los Angeles Lakers, Isaiah Thomas has only allowed 0.762 points per possession by Synergy metrics? But the Purple and Gold have ceded 114.4 points per game since acquiring I.T. at the deadline, and they have a defensive rating of 114.9 when he’s on the court. That would put them in last place for defensive rating when extrapolated across the season.

While these statistics aren’t perfect by any measure, there really is no way to adequately quantify a player’s impact on the attempts he defends. Luck is, and always will be, a huge factor in whether the shot goes in, not just one-on-one defense and contesting shots.

The issue with trying to quantify value for defensive impact is what I call the deterrence dilemma. Statistically, we can only account for the shots a player takes. But really good defenders—the ones who cover ground and can stifle ball-handlers or those trying to score—don’t allow their man to get a clean look at the rim.

More simply put, how do we account for shots that aren’t taken because of good defense?

That’s where I get stumped in a statistical argument, and where I really have no answer for how to find the adequate explanation. I watch plays like this one, where Jrue Holiday essentially discourages Kentavious Caldwell-Pope from taking a shot, and think about how anyone watching the play can see the impact he has…but also how a set of raw data won’t quantify it:

Individual defensive ratings illustrate how the team fares when that player is on the floor. But so many factors are beyond a contributor’s control  and still factor into the statistic. Who does he share the floor with? Is he going against other starters or bench players? Is he playing in meaningful minutes or in garbage time? Are those garbage-time minutes to his favor or detriment in terms of effort? And, most importantly, how much responsibility does that player bear for the team’s defensive rating?

Team defensive metrics are incredibly important, and the aim of any statistic (at least from a team perspective) should be to assign responsibility to players as individuals to help them improve and prepare to fit into what the team needs. How can we sit here and say that, just because primary players aren’t shooting a high percentage against Isaiah since he joined the Lakers, that he isn’t an overall negative for their defense?

Statistics are wonderful, and the game of basketball has made a great deal of progress by investing in this type of thinking and using it in meaningful ways. That much is crystal clear after seeing the incredible impact the Sloan Analytics Conference has had on the basketball community. But defensive statistics cannot surpass film and understanding of how to assign responsibility for what occurs on the floor, especially when we have not yet perfected how to assign responsibility through data.

I hope we can get there at some point, but we aren’t there yet.

2. Wayne Ellington, Firing at Will!

Over the last 15 games, Miami Heat wing Wayne Ellington has launched 126 three-point attempts. That’s more per contest than the likes of Devin Booker, Lou Williams, Kyrie Irving, Bradley Beal and Klay Thompson. But Ellington, unlike the scorchers named above, is shooting 33 percent from the field during that span.

Chucking up so many attempts during a fairly cold spell takes some chutzpah. In his defense, head coach Erik Spoelstra and others around him ask Ellington to take attempts with a high degree of difficulty. Take this action, a common ATO set Spo runs to get Ellington a look. It’s a brilliant design for how it toys with the help defense, but it puts the onus on Wayne to square up to the basket and fire away pretty quickly:

Beyond that, Ellington has probably earned a decently long leash with how he’s shot this year. Despite the 15-game sample, Wayne is at 39 percent from three and 40 percent from the field on the year. The reintegration of Dwyane Wade into lineups has added one more non-shooter to the rotation, meaning Miami needs to rely on these shots from Ellington. He’s not going to stop taking them anytime soon.

Hopefully for the Heat and their faithful, he’ll start making them. Ellington has been a role player for a long portion of his career, not used to the rigors of logging as many minutes as he has this year. The 26.4 minutes per game is a career high, and he’s been playing even more since Dion Waiters went down for the season. His 451 three-point attempts are already a new best. The dude is a straight gunner, but he’s also a role player personified.

It just so happens that his role is to make deep, contested, difficult three-pointers.

3. The Golden Ball Screen

Alright, I’ll bite. The Golden State Warriors are damn good at everything, but that dang Kevin Durant-Stephen Curry ball-screen combination is pretty much unguardable.

One of the reasons I’ve always loved the modern Warriors is the insistence of head coach Steve Kerr to run ball-movement-heavy offenses and ensure everyone gets a touch on almost every possession. The theories behind it are simple from a coaching perspective: The more the ball changes sides of the floor, the harder it is to defend from a team standpoint. The more player movement there is, the more opportunities there are for the defense to botch an action. And the more each guy feels like he contributed something positive on offense, the apter he is to be locked in on the other end.

Somehow, the Warriors have made it to three straight NBA Finals and won two championships without leaning heavily on the pick-and-roll, despite the lethal nature that it might have. As the Warriors trot through the regular season and focus on not tipping their hand too heavily, it might be time to open up the discussions on how frequently we get to see the NBA’s most unguardable action.

It’s not like ball screens haven’t been friendly to the Warriors, either. They score on 48.2 percent of plays where a ball screen results in a shot; no other team is above 45 percent. But that Durant-Curry pick-and-roll combo…holy moly. Both are among the best in the league at creating off a screen, and the threat of two future first-ballot Hall of Famers converging in such a set is a nightmare for defenses.

At the end of quarters or in controlled late-clock situations, Kerr has begun to dial up a few more of these sets. Durant and Curry flashed their magic at the end of the first quarter against the Washington Wizards this week:

Kerr puts these two in a dynamic action but doesn’t sacrifice the off-ball movement he holds so dear. Patrick McCaw runs off a baseline stagger, an action that not only occupies the defense but provides a secondary option if, somehow, a defense figures out how to solve the KD-Curry conundrum.

As we inch closer to the postseason, the stylistic differences between the Warriors and Houston Rockets—the two top teams in the league—will come underneath the microscope. For now, the rarity of these plays, and their daunting level of success, leads me to believe the Warriors are still the clear favorites.

4. Assessing the Wall-less Wizards

A lot has been made about how the Washington Wizards are playing since John Wall went down with an injury, both in terms of style and result.

Washington is now just one game behind the Cavaliers for third in the Eastern Conference. It’s 9-4 since the point guard hurt his knee and was expected to miss six-to-eight weeks, and it’s climbed out of a hole to position itself well for the postseason.

They’ve done so on the back of strong individual performances from the likes of Bradley Beal, Otto Porter Jr. and Tomas Satoransky while playing in a fashion they never had with Wall in the lineup. It’s led some to ponder whether Wall’s absence brings a case of “addition by subtraction.”

From a coaching perspective, the recent change in Washington’s playing style is born out of necessity, not out of desire. Wall was the catalyst for such a large part of the offense, playing with the ball in his hands as frequently as any star player in the league. Head coach Scott Brooks relied heavily on Wall to create, especially out of the pick-and-roll, to the point where he rarely played without the ball. His Synergy play-type profile is truly a marvel—he’s attempted only one shot off a cut and three coming off a screen this season. He’s attempted 604 shots.

While the spot-up category is also fairly low for Wall, you have to dive deeper into those numbers to find how many true catch-and-shoot attempts he’s launched. The answer? A paltry 55. Fewer than 10 percent of his shots come off opportunities created by others. That’s the definition of ball-dominant.

Since his absence, the Wizards have posted some awesome ball-sharing metrics, including assists-to-makes ratio. Twenty-seven assists on 34 made baskets in a win over the Oklahoma City Thunder, 35 to 46 when they thrashed the Orlando Magic and 35 assists on 43 buckets when they took down the Philadelphia 76ers. Generally speaking, garnering assists on 70 percent of total team makes is considered a very good rate for sharing in the creation of offense. Washington has been hovering around 80 percent in some contests.

Why? Think of it like a football team that loses its star quarterback, then turns to the run game to pick up larger chunks of offense. The playbook might shift week-to-week, including more trickery in their runs and plays designed for backup runners or third-down backs. Time-of-possession rates will increase, and the ball will be spread around the offense a lot more frequently.

That shouldn’t diminish the value of the quarterback upon his return.

Essentially, the Wizards are playing a fundamentally different style of basketball without John Wall, and the residual effect is to get different players more touches as playmakers. Brooks has called for more true motion sets, like Motion Weak (a San Antonio Spurs staple, and a portion of his playbook in OKC) or Horns entries to play through their bigs. In the last game of which Wall was a part, the Wizards utilized the ball screen to create offense 47 times, per Synergy Sports. They only went to it 26 times in their win over Philadelphia last week.

Regardless of their playing style, Wall as a singular talent is a player who needs to be placed in ball screens in order to be maximized. Brooks shouldn’t be blamed too greatly for what could be seen as holding his group back by letting his point guard run the show. If you have an MVP-caliber quarterback, you’re going to let him sling it around the field.

What we’re seeing now is the rest of the team, fresh and capable of serving as quality playmakers, stepping up and taking the rest of the league by surprise. They’re blitzing others that expect the Wizards to run the same sets in a methodical fashion. We don’t see the second, third or fourth options off motion sets when Wall is in the game because he can just blow by his man and create off his athleticism. There’s no reason for a coach to call motion sets when Wall can get to his spots any time he wants.

Washington is only 14-10 in all games this season without Wall, hardly enough to call the 36-26 Wizards profoundly better when their superstar is off the floor. Satoransky, who has been unbelievable in Wall’s absence, has been playing at a completely unsustainable rate. In the 13 games he’s started since the Wall injury, he’s shooting 52 percent from downtown—a pretty torrid pace for a guy who was only at 24 percent last season and had just four games with multiple makes from deep before February. He’s due for a cooling period, and these Wizards will come down to earth.

When the shots stop falling, the assist rates will likely dwindle, as well. There’s hope that the Wiz play a more fluid style once Wall returns, and they can find some success doing so. If they can buck the trends and stay hot throughout his absence, it feels like Brooks will have no choice but to steer clear of the Wall-centric pick-and-roll offense.

As for the former No. 1 pick, he’s netting 1.145 points per possession on his catch-and-shoots this season, a respectably positive number. There’s no doubt he hasn’t played up to the level he’s capable of this season, especially on the offensive end. But let’s cool the jets on proclaiming the Wizards better without him. Thirteen games is a small sample, and practically everyone else on the roster has played far above their ability levels over this stretch. Wall is going to be vital to their postseason run this year, no matter how Brooks works to reintegrate him with what is a drastically different group of teammates from the ones he last played with.

5. Look out for Charlotte

Laying in the weeds on the outside of the Eastern Conference playoff picture are the Charlotte Hornets, just 4.5 games behind the No. 8seed. They’re only 8-7 over their last 15 games, but their core guys are starting to play better. Kemba Walker is averaging over 26 points while shooting better than 50 percent from deep. Dwight Howard keeps ticking away with 16.7 points and 11.5 rebounds per game. The ultimate wild card for this team, Nicolas Batum, has come back in a major way, putting up splits of 13.3 points, 4.9 rebounds, 6.1 assists and 37 percent shooting from deep.

Now that the Hornets are healthy and their key guys are playing like key guys, the role players can settle into their normal spots. Jeremy Lamb is a team-high plus-4.1 over the 15-game span, orchestrating in a much more comfortable role on the second unit. Cody Zeller, who is also finally healthy, is back to doing Cody Zeller things and just making winning plays. Charlotte is 7-4 since he’s returned.

Their schedule is pretty favorable as well, with only one game remaining against Toronto and one against Cleveland. They get four head-to-head contests with the Sixers to try and gain ground, as well as two with the Indiana Pacers to wrap up the year. But the kicker for Charlotte is a whopping 10 games left with teams involved in the league’s race to the bottom. That slate itself should propel the Hornets right into the thick of things out East.

If they can sustain their hot shooting, the schedule and health might allow them to add another dimension to this Eastern Conference playoff race. This Hornets squad has endured a lot this season, from injuries to players to the extended absence of their coach. It’s difficult not to root for them down the stretch, especially as so many other teams in the East are frustratingly failing to secure a grip on a playoff spot.

Unless otherwise noted, all statistics are courtesy of Synergy Sports Tech, NBA.com or basketball-reference, and are current as of March 1, 2018.