First, for this glitch to work, you must complete theses steps:

1. Have a game completed with Jonathan at hard (any caps will do, but 1 is recommended for the purpose of the glitch).
2. Go on jonathan's new game + and press A once.
3. When it shows the difficulty to use, press B.
4. Go on an empty save file, press A.
5. Choose any of the characters and start the game.

If you try to defeat enemies, you'll notice you do the same damage (If you had the str boost from the LV1 Cap at hard) than if you were LV40, but at LV1!