Let's say you equip a persona who repels fire, and you're fighting an enemy with that same property. If you use a fire skill, what happens to both of you? Does either of them null it once it repels? It would be funny and ridiculous at the same time if there was just an endless volley of fire being reflected.
This is just a random thought that's been in my mind for a while.
HMM....Just end up a stalemate
The one that would reflect a second time just nulls it. I know because it happened to me a lot for some reason.