Suppose you have a player who has a two-handed weapon A and another two-handed weapon B. He can use either of them without any problems, but not both as he only has two hands.
With the card "Cheat!" he can use both of them. But now he gets a third card C, also two-handed, which he likes to use against a monster. So for one round he puts A and B in his back-pack (it's still in front of the player, but he does not use A or B, but C). Can the player in one of the following rounds use A and B (together, without C) again?
I thought Cheat! would disable the "checking-mechanism" once, when the card comes into game. After that, when anything else changes something with the card it would have to be discarded again. However, I'm not sure if that makes sense. For example, if you used Cheat! because the weapon is only usable by a thief and you are a blogger, it would seem strange to me if you lose the weapon because you changed to a kid.