Couple things - I've never heard about Mahomes off season workouts. I know he has 2 rings, but still never heard about them.
I'd honestly be a bit surprised if Allen didn't have some kind of off season workouts with the new guys that have been brought in. Not just the wr's, but we have a new center too, which is a pretty important position for Allen to succeed
I thought in the first half of last season, Allen was forcing the ball to diggs too much. Obviously Diggs had some really good numbers, so it wasn't necessarily bad, but I think about how both Diggs and Shakir, and maybe even Gabe, could've been more effective. Though, our 5-5 record isn't completely on the offense. The defense had some massive blunders (1st Patriots game)