That was a bad assumption. He entered a team with, possibly, the most talent he's been surrounded with on all three phases in his entire career. If that's the basis for arguing that Brady hasn't outplayed him, then other posters may want to re-think their position.
IMO, the "new offense!" thing is overplayed. It's the same exact timing offense that he's in with some of the best players surrounding him since Marvin Harrison and Reggie Wayne were in their primes. Thomas is emerging as one of the NFL's better WR's, Decker is solid in all phases, and he has a couple of guys with a lot of continuity coming over from Indy. Further, his offensive line hasn't been interchangeable as the Pats has. And, even with all that considered, the Broncos offense simply hasn't looked good at times this season until teams go into a soft zone in the 4th quarter where Manning begins to pick them apart. "Vastly" may be a stretch, but anybody that's watched these two quarterbacks play knows that Brady has outplayed Manning. At that, I don't think it's even arguable unless you're being a contrarian for the hell of it.