My version have the same effect. I did say it either give you all key items or zero out your key items. One that don't zero out key items can be made. I might do it. It's just a bit of extra effort to copy what you already have to another place.
Backing up save should always be done when you cheat. Especially when the code is made by people who don't play much.
PS: I think there are a few exceptions but most of us don't play much. One's time is finite. You got to choose whether to make code or to play game.
