Actors' performances in films are enhanced in a million different ways, down to the choice of camera shot by the director - whether it's in slow motion or whether it's quick cut - or... the choice of music behind the close-up or the costume that you're wearing or the makeup.
If James Franco's wearing a costume, and I'm wearing a motion capture suit, we don't act any differently with each other because of what we're wearing. We're embodying our roles.