I feel like you are looking way into this, I don't know how often you are in-game but for someone who is in-game a lot, this addition won't affect much, it is one of those features you wouldn't have to use yourself so arguing about it taking your focus away from the actual situation isn't that great of an argument; especially for players who are able to go through outcomes rapidly or anticipate better (the competitive players). You wouldn't exactly be seeing what your opponent will do, you would just be anticipating the outcome of them switching their grabs. I used to have a glitch on older versions of TB which tested just this feature and it was interesting to have the option to see how I would fly if neither my opponent and I grabbed. For a game built on anticipation, this feature doesn't hurt it at all. It would definetely be used in the competitve scene.