You need to have a detector, since you can't get vision from P12, you could also use a computer player with a detector and have them vision the players.
so it can be beaten by a prepared pro, even in macro games, if only barely. the muta micro in particular seems really hard to handle for protoss ground though. In the open goons can't catch them, in the base they trip over buildings, it just instantly flies out of storms and they fly circles around archons. Mass cannons do work, but can't cover the whole map with it. Probably need mass corsair to counter and hope you can outmaneuver all the scourge.