I'm sure it would work similar to the Amulet Coin in that so long as the Pokemon participates, it would take effect. The intangibility of it would be what makes it not so OP as just giving them all back. But I can see where you are coming from.

Really? I never saw it that way. In fact, I never really bothered to question the point of money in the game, other than to provide a reward, and to make you work toward that specific TM/Rare Item. I never really cared about the money except in the early stages when there wasn't much to use, which is where the item would be most effective. Maybe I played the game differently than most of you, but the money didn't seem like that big of a deal to me. I wasn't forced to make decisions. In real life, I'm terrible with money, so that probably has something to do with my views...