freeze plugs only go bad when the engine has water in it and it freezes and has nowhere to go except out of a freeze plug. overheating will cause the radiator hose to blow, overflow tank to spew, or radiator cap to fly off at a very very very high velocity.
like beefhole said, internal coolant seal. i believe it would be the outer seal on the rear of the rear rotor housing that would cause it to leak out of the rear so much
91 s5 n/a-turbo boost = *****