In one year, his average made FG distance went from 3.2 feet in San Antonio to 12.5 feet in Atlanta. It looks like he discovered he has a jump shot, or more likely Bud would let him shoot it and Pop wouldn't.
In the process, his TS% fell from .645 to .599, which is still quite respectable (and exactly his career average) and significantly better than Nurk's career best .528.
For comparison, Nikola Jokic, the $148 million man, had a TS% of .603 last season. Obviously, Jokic can do a lot of other things Dedmon can't, but it does show that Dedmon isn't a complete offensive zero.
BNM