My guess is that he meant "play the devil's advocate" and got it mixed up half way through. That happens to people all the time with metaphors, especially when

My guess is that he meant "play the devil's advocate" and got it mixed up half way through. That happens to people all the time with metaphors, especially when our minds are hard at work on the actual problem at hand, sometimes ending up pretty funny, like "we'll burn that bridge when we get to it."