By “couldn’t” I didn’t mean “would be physically incapable of”, I meant “certainly wouldn’t”, which is what I took your “would not be …” to be saying. “Usually wouldn’t”, I have no disagreement with.
By “couldn’t” I didn’t mean “would be physically incapable of”, I meant “certainly wouldn’t”, which is what I took your “would not be …” to be saying. “Usually wouldn’t”, I have no disagreement with.