How is this going to work in practice? Unless it prevents you ressing someone while a res is already being cast, you're still going to get multiple people trying to res the same guy (and probably having already blown their Swiftcast to do so), and if it's done so you can't even begin to cast a res on someone who has one being cast on them, I can see an awesome new way for people to troll CT raids even more than they already do.