This is a casual discussion. That's why I said the exception was implied. If someone were to say, "deity X is omnipotent," he would not say, "deity X is omnipotent, with the following exceptions: he can't create both an immobile object and an immutable force to coexist, he can't be taller than himself, he can't change his own nature, etc. etc." Those things are understood - they are logical impossibilities. To demand all absurdities be allowed for in every definition would be to demand all discussions be needlessly verbose.