Listen, when a functional Democrat is held high as an example of the Republican Party brand, as happened in 2012, the fact that Cruz is on our side is small comfort! Something is very wrong with that picture. But hey -- I vote Republican when the Republican is limited government conservative. When the Republican is a functional Democrat, forget it, Cruz's promises notwithstanding.
Whether or not a third/second party is necessary, I don't know, but I do know that if the GOP nominates an anti-Cruz Republican for the presidential, all bets are off.