This is ludicrous. He shot poorly in Summer League before his injury. It was his lack of size, pace, and athleticism at the pro level that had him line driving shots well before his finger injury. Can P3 make him a better athlete? Better hope so. Ever since summer league, his jumper has been releasing flat, unlike his FT's, and that's because a jumper requires one to jump, and the kid couldn't, because he was tired, because he is a poor athlete, at this point.
And saying "he slowed down the offense so Hayward could be the primary ball handler in the half court" is really looking through the blinders. Hayward wanted to run. Trey said he played slow, because he wasn't comfortable playing fast, on locker clean out day.