People act like YAC has nothing to do with the QB, but if you don't hit the guy on time in stride you almost never get any YAC.
Dak's problem isn't absolute arm strength. It's inconsistent technique, which leads to inconsistent ball placement. It's going to sound like a lazy comparison, but Dak has always reminded me a little of McNabb. McNabb was always a guy who was inconsistent with his timing and precision but rounded out into a good NFL starter. Of course he also had much better offensive coaching... I don't trust Andy Reid in the 4th quarter down 4 with 5 minutes left, but I do trust him with developing QBs the other 6 days a week.
It is funny how Cooper's yards per reception and catch rate jumped up when he went from Carr throwing to him to Dak throwing to him. Hmmm.