He actually shot 70% in his first or second season I think. As I said, he changed his form which helped his 3s but messed up his free-throws. I guess you would still take it but it hurt today. I'm actually surprised more teams haven't hacked him. I expect Houston to employ it again if they need it - but I don't think they will.
Looking at his stats, he shot 70% his rookie season on 0.3 attempts per game which is a small sample size. Then 48%, 61%, and 42% respectively. His career FT average is less than 50%. He's also only shooting 26% from deep for his career (shot 25% this season). His form doesn't look terrible, though, so like with most players who shoot poorly, it has to be partly mental.
Poor Russ. You can see why at times he chooses to shoot so much. Houston's bench is ridiculous, Gordon, Williams, and Nene. Can't believe anyone actually thinks the OKC support cast is in the same stratosphere. Some interesting matchups in the first round but you can't help feeling it's all leading up to Cavs-Warriors again.
I think it's mostly the system and coaching. Houston's team is built around Harden, whereas OKC's was set up for KD, but the gap between the quality of players isn't ginormous, in fact, many preseason reports projected OKC to have a better season than Houston (some were posted a few pages back). On paper, Oladipo, Adams, Kanter, and Taj are good role players.
The thing is that the likes of Shaq and co. weren't very skilled in the game. They just happened to be stronger and bigger than everyone else and so overwhelmed them but they weren't much skilled.
As Stephen A. Smith would say, "that's blasphemous!" You need to watch some film of him in the 90's to early 2000's and not remember him for his days as a Cav, Sun, or Celtic. He wasn't just pure brute force; he had a whole repertoire of moves: he could back you down at will, utilize the drop step, he had the baby hook, a nasty spin move (aka Black Tornado), the Dream Shake, he could dribble the ball as good as anyone for his size, had the quickness of a guard (especially in the 90's), very underrated passer, etc. He played in an era ruled by centers (Hakeem, Robinson, Ewing, Zo, et al.) and still dominated. Sure, he wasn't as silky smooth as The Dream, or have the perimeter game of a Ewing, but inside the paint, he was unstoppable while constantly being double/triple teamed. He was also fouled like nobody's business, but since he was the biggest, they weren't called.
I didn't like that he wasn't fully committed to basketball, using the regular season, not training camp/preseason, to get into shape. He didn't take himself seriously and liked to joke around (not really a negative), but he always delivered when it mattered. You don't carve out a two decade career, playing around a decade as the best in your position, without being skilled. They changed the rules because of him. MDE.