"That may be," Strange admits. Because there's no hiding just how miserable and how angry he was when he saw Childermass with Amanda. There's not even a point to try and argue that he's happy when it's so obvious he isn't.

"But now I have access to more knowledge and soon more power than I'd have ever dreamed of. It's worth it."

He hopes. Going mad, repeating the actions that the English magician took have certainly unlocked more memories, but nothing yet's unlocked just how the other Jonathan Strange does the magic. It's no use to remember traveling though mirrors and turning people into cats if you have no idea how to do it in the first place.