So the girl learned that she has an issue in the basics, and needed to have it pointed out to her or see it through how someone she teaches adopts the same mistake. And the guy simply needed some physical exercise so he could stay focused for longer.
Did the fat ugly bastard actually foresee this solving both of the school's "geniuse's" issues? I get that the shogi coach might have talked with him about it, despairing that his genius needs more exercise, and the swim coach hatching that plan in response. But I really have a hard time seeing the guy predict that the swimmer would realise her issue if she coaches someone (did the school actually have a third genius in him?). And why didn't he just tell her outright (hell, why isn't looking at recordings already part of their schedule, if they are that serious about the sport)? Or ensure that she actually coached the guy (and he actually swam), for that matter?