[LeRoux Strydom]

My understanding: defending an often indefensible position (like literally defending or advocating the devil in a court of law) for the sake of allowing the other side with a morally more defensible position to strengthen its arguments and remove all doubt. Again, you don't necessarily have to agree, but simply to put the contrarian arguments within the "rules of the game".

I'll have to remember its historical origin, thanks for that, tchanson.

LeRoux