Jonathan Strange & Mr Norrell question

If nobody can find a good answer to this question, I think you might have found a major plot hole in this book that a lot of fans have missed.

I took the answer to be in the nature of the curse. It ultimately wasn't the Man with the Thistle-down hair that placed the curse, but the mountains and air and rivers at the request of the Man. I also believe that was the triggering event to remind Jonathan that those elements also had alliances with humans/England.