The feather-fall potions were protection against a case that wasn't supposed to happen. Harry doesn't take precautions so that he's licensed to need them, he takes precautions so that people don't get hurt. Hermione falling wasn't supposed to happen -- he endangered her for the sake of a game. He raised the stakes farther than they were supposed to go, and it was someone else who could have gotten hurt.
ETA: There is now a third thread, so send new comments there.
Since the first thread has exceeded 500 comments, it seems time for a new one, with Eliezer's just-posted Chapter 33 & 34 to kick things off.
From previous post: