I guess the point of Be2 in the first game is to be able to take the knight on f6 without black being able to play dxc4 with tempo (if 14.bxf6 dxc4 15.Bex7 Cxd3 16.Ba3 Qb7 17.f3 Bb5 maybe holding on to the pawn, and the problem with castling can be solved with ...e6, with white being unable to attack that possible weak pawn with rooks).
If instead of 15.Bxe7 white played Bxc4, perhaps ...Bxf6, and the plan of ...Qb7 might create some weaknesses in whites position.
If the same sequence happened with the bishop on e2, then after 14.bxf6 black has no choice but to take on f6 back, and cxd5 would be achievable for white with a better position, also ruining the pressure that could have been exerted on a8-h1 diagonal for black.
Please tell me if i am missing something...