...I think a lot of business deals start to make more sense once you "de-gamificate" them: you show the other part that "gaming" tricks won't work in this negotiation because you're on the same level as they are on using them, so both parties can now concentrate on a compromise offer that provides the best "real value" for both! I know, "make more sense" doesn't mean "make more money", but you end up with more satisfied customers and you end up doing business in segment of the market where there's less "gaming" to waste your energy on, so you can concentrate on improving and diversifying products or forging better customer relations.
Maybe the best way to "win" a negotiation is to "kill" it, i.e. turn it into something that's no longer a negotiation, where it's obvious that no one side can "win", no fucking way, so both parties can concentrate on the best possible compromise. (Yeah, the "pro gamers" will never want to do business with you again an will try to keep you away from any of their future businesses and negotiations, because your ways are "bad for business", but maybe this is not the segment you want to play in in the first place!)