Whatever Manziel was trying to prove in the spring league, I don't see it.
Rusty... playing behind a disaster of an OL... hanging his receivers out to dry... ugly.
Offer him $80k and incentives.
I dont think he was trying to "prove" anything - I think he has just been sitting on the shelf for so long that he needed to get back into the game to some capacity to get back in the football "zone".