This week's mailbag features your questions on LeBron James' offense, Golden State's stars and more.
You can tweet your questions using the hashtag #peltonmailbag or email them to peltonmailbag@gmail.com.
"Why do the Warriors seemingly destroy teams when Curry gets hot but not when Durant gets hot?"
-- can_wien07
This question was posted on r/NBA in the hopes that someone would dig deep, so let's do it in the context of the ongoing debate over whether the Golden State offense has featured too many Durant isolations against the Houston Rockets.
First, the idea is accurate, even when we account for potential confounding factors like the fact that starters tend to play more in close games than blowout wins. The Warriors are 5-4 in Durant's nine best games by John Hollinger's game score this season, as compared to 8-1 for Curry. And they're winless in Durant's six games using the most plays per 36 minutes. (They're 25-1 in Curry's top 26.)
That record is partially about Curry's injuries; he missed three of those six games. Still, when we look only at games in which both Curry and Durant played, there's a negative relationship between Durant's plays used per 36 minutes and his teammates' efficiency, as measured by true shooting percentage.
By comparison, Curry's usage appears to have no consistent effect on his teammates' efficiency in games both players play.
Not coincidentally, the Warriors assist on a higher percentage of their baskets when Curry uses at least 30 plays per 36 minutes (68 percent) than when Durant does so (65 percent).
So is this an indictment of Golden State's strategy in this series? I don't think so. First off, when we look at how often the Warriors run isolations according to Second Spectrum data, there's actually a tiny positive correlation between how many isolations they run (both total number and per 100 possessions) and their offensive rating in the game -- one that grows a bit stronger when we account for the opponent's regular-season defensive rating.
In the 10 games in which Golden State has run the most isolation plays per 100 possessions this season -- including all six games in this series, plus the Warriors' loss to the Houston Rockets on opening night -- the Warriors have scored 8.7 more points per 100 possessions than their opponents allowed during the regular season, as compared to 6.1 overall this season.
I don't necessarily think this is an indication Golden State should rely more heavily on isos in Monday's Game 7, but I think the greater correlation with opponent-adjusted offensive rating is a key tip-off. The Warriors tend to isolate more against defenses that are good enough to take away the system baskets they'd prefer to get, meaning their offense will probably not look as good, whatever Plan B they use.
There's a similar chicken-or-egg aspect to the original question: Does Durant take over because his teammates are struggling, or do they have a tough time getting going when Golden State's offense revolves around Durant isolations rather than ball movement?
It looks like maybe a little of both. According to Second Spectrum tracking, Durant has averaged 22.9 shots per 100 chances (or team plays) overall this season, including the playoffs. In his six highest-usage games, his shots per 100 chances start above average in the first quarter (25.3) and go up from there, peaking at 30.3 in the fourth quarter.
The NBA Advanced Stats breakdown of usage rate by the margin on the scoreboard is also instructive for understanding the difference between Curry and Durant.
Curry's usage rate generally goes up with the Warriors' lead, while Durant's goes down. So Durant tends to use a higher share of Golden State's plays when the team is already down, while Curry tends to use more when the Warriors lead. I think the evidence suggests that the negative relationship between Durant's production and team success is mostly about this factor, but that the Golden State offense does tend to work best when Curry serves as the engine and not Durant.
Do you think LeBron is now better offensively than ever ?
— LeBron James fan (@mp0230) May 10, 2018
Coming off a season in which LeBron James averaged a career-high 8.9 assists per 36 minutes and the fourth-highest points per 36 minutes of his career (26.8) while shooting 54.2 percent from the field, this notion is understandable. However, I still don't think James is quite as good offensively now as he was in the last two years of his first stint in Cleveland.
Part of the issue, as I've discussed before, is how rising pace and improved offensive efficiency set the bar much higher. As part of my wins above replacement player metric, I estimate the offensive rating for a player plus four league-average teammates. James' 2017-18 offensive rating of 114.0 is the third-highest of his career, and higher than that of any season he spent with the Miami Heat, but when we take out the average offensive rating (106.2), it drops all the way to seventh.
Relative to league average, James' .604 true shooting percentage in 2009-10 was nearly identical to this year's actual .621 mark. And back then, James was responsible for 44 percent of the team's offense between his own usage rate (33.7 percent of the Cavaliers' plays while on the court) and assists (handed on 10.3 percent of plays), as compared to 42.7 percent this season. Add in that James turned the ball over less frequently relative to his plays used back then and I think 2009-10 was the best offensive regular season of his career, ahead of his super-efficient play in 2013-14 with the Heat and his performance this season.
How about the playoffs? LeBron's been even better relative to league average, putting up an offensive rating (again, for a team with four average teammates) 10.0 points better than league average. And yet that's only good for fourth best in his career; James' offensive rating was 12.1 points per 100 possessions better than average in 2009, when the Cavaliers lost in the Eastern Conference finals, 10.9 points better in 2013 and an astounding 16.8 points better in 2014, when his .668 true shooting percentage was best in playoff history among players with a usage rate of 30 percent or higher.
The moral of the story is the toughest opponent for LeBron to top has often been the standard he has already set.
"One thing that always bothered me. In terms of calculating scoring margin, shouldn't games that go to overtime be counted as "0," rather than whatever the margin is at the end of the game? It is misleading to count a win by six points in overtime as a six-point margin when in reality it was dead even after 48 minutes, and is certainly closer than a game that ended in regulation with, say, a five-point margin. Would have just a minimal effect on overall scoring margin but isn't this still mathematically and logically sound?"
-- Tarek Mohamed
Well, I think the question here is whether overtime results are representative of ability. If so, the fact that the game is tied after 48 minutes is no more meaningful than whether a game is tied with five minutes left. We wouldn't want to cut out those last five minutes of regulation and shouldn't cut out overtime, either.
So are overtime results representative? A few years ago, Ken Pomeroy studied their predictive value in college games. He found that in terms of predicting rematches in conference play, each point of margin in overtime translated into an additional 0.27 points of differential in the other game, as compared to 0.36 points for each point of margin in regulation.
I think that makes sense and would likely carry over to the NBA. The end of close games is probably less predictive because of intentional fouling and other measures to catch up that can produce misleading margins. Still, these results do have predictive value, and throwing them out entirely is a bad idea.