Too strong. The author isn’t arguing for the removal of academics from the teaching process, but rather for allowing executives to be included. So she doesn’t need to assume that academics have no valuable experience. She just assumes that they’re missing some kinds of experience or knowledge that students need and executives have.

Too strong. One premise is that hypothetical case studies are used “too often,” but that doesn’t suggest that they’re the only case studies used. It’s possible that academics use real-world case studies too—just not often enough. So the author doesn’t need to assume (B).

The author doesn’t suggest that academics can’t teach the curricula; in fact, her conclusion specifically says they can. So she doesn’t assume (C). (To the contrary, she must assume that academics are capable of teaching the curricula.)

This compares academic training outside of business schools to within business schools. But it doesn’t matter how responsive academic training is to the needs of business. The problem is that management training isn’t responsive enough, and the argument is purely about how to fix that. There’s no need to assume anything about any other kinds of training.

The author never explains why executives, specifically, should be setting management curricula instead of academics. She must assume that executives can provide insights that academics can’t. Otherwise, there’s no reason to conclude that executives should be involved.