As Bill Simmons would say if it wasn't for a bunch of horseshit: "Nobody believes in us" is the most powerful force in sports. It turned Derek Anderson into a good quarterback earlier this season.
Almost every elite quarterback that isn't a Manning has had some moment of adversity. Aaron Rodgers infamously fell in the draft. nobody expected Tom Brady to become who he became, Drew Brees was passed over in free agency in favor of Dante Culpepper, while Phillip Rivers had to back him up. Big Ben had big dreams of a big college career but wound up at Miami of Ohio. The list goes on. Maybe this is what RG3 needs to "prove da hatas wrong" or whatever you cool kids call it.
It would also help if he would stop eating the same food that give Justin Tuck the fuel he needs to dominate the game, because it clearly doesn't work.
He just needs to have faith and use his awesome deep ball again. If dude plays Bomberman with DeSwag he'll be unstoppable.