Marcus Smart arrived at the Celtics preseason training camp 20 pounds lighter and a jump shot that looked 60% smoother. The new and improved skinny Marcus, or Diet Cobra, if you will, connected on three-point shots with ease in the preseason, but has reverted to his old shooting clip in the regular season.

Harsh as it sounds, Smart might be the worst modern three-point shooter. Eight games into his fourth season, Smart is shooting more threes than ever before (by a very narrow margin), taking 4.6 per game and scoring on 1.4 of those attempts on average. Again, Smart’s shooting percentage from deep is below 30 percent while playing a prominent non-starter role (stats via basketball-reference). In a world where NBA big men are adding a three-point shot late in their careers, you can never rule out Smart, but his lack of progress in respect to his shooting compared to his teammates (specifically Jaylen Brown, Jayson Tatum, and Terry Rozier) means I won’t be holding my breath waiting for skinny Smart’s breakout shooting year.

So what happened to the “new” Smart? Did the magic of his new three-point touch wear off? Here’s what I’ve noticed: Marcus Smart does not stay consistent with his shooting form. If you look at how he shoots from year to year, and sometimes game to game, he has constantly changed how he shoots. Here’s a shot he hit against the Oklahoma City Thunder in 2015:

This is what most of Smart’s three-point shots used to look like. He starts his motion with the ball down low, brings it up over his head, and holds his follow-through after launching a rainbow. Notice how his feet are about perfectly square with the basket. Now, here’s Smart hitting a shot in the 2017 Eastern Conference Finals against Cleveland:

It looks a little bit cleaner. Most of his form is the same, but he doesn’t bring the ball up over his head completely before releasing the ball. Smart was predictably streaky all year but hit a nice stride behind the arc in some late-season games. Next, a 2017 preseason three against Charlotte:

Again, very similar, but slightly adjusted. His balance looks great here, compared to how he starts his shot in the first video with flat feet. Smart hit three triples this game, and it appears that he is angling the right side of his body towards the basket a bit more than before in his shooting motion. Maybe that helped? Finally, here’s a shot Smart hit early in the 2017-18 season against Miami:

For such a deep shot, Smart actually jumps a little less and releases the ball bit further out than usual. Compare this to the OKC video, where Smart starts his shot well behind the arc and lands with both feet in front of it. In Miami, his feet land almost exactly where they started. This, in my opinion, is his best looking shot out of the four I’ve shown. It’s quick, it’s clean, and I think the added arm extension helps guide the ball to the basket a little better. I’m not sure why he wouldn’t stick with it.

It’s not unusual for a player to tweak their shooting mechanics year to year. Avery Bradley tightened the screws on his shot, as did Terry Rozier. And sure, players figure out their form in the middle of the season sometimes. That’s fine. I’ll even submit the fact there are around 20 other players with absolutely ghastly three-point shooting this year, some of which you would expect much better from, including John Wall and Mike Conley. But is it even fair to compare Smart to those players? Probably not, but then that leaves him in the company of Frank Kaminsky, Tyler Johnson, and the like. Are we ready to accept that the heart and soul of our beloved Celtics is as good a shooter as middling role players on super-middling teams? Also probably not.

All I can conclude is that Smart is confident, but not comfortable, shooting from distance. He’ll never shy away from an open look even if he doesn’t trust his own form. Otherwise, I can only speculate. Maybe a consistent form isn’t a point of emphasis for him. Maybe nobody else has noticed. Perhaps his form is dependant on how fresh his legs feel. Whatever the case is, it’s not a problem you want to have in a contract year.