Good question. I think it could have a big effect. I only use mechs on antelope so it isn' t an issue. Last fall I spent a very wet and cold day in the deer stand and the jaws on my release froze. Had to put it in my mouth to get it to work again, ten minutes later would be froze up again. Once it was wet there was nothing I could do about it. Going by this I would say that a mech would not perform well under those conditions. I keep my release covered now when wet and cold but you can' t keep a broadhead in your pocket.