What Does 'Good-Good' Mean in Golf?
To further explain the parameters of "good-good" on the putting green: It is used in a situation in which Golfer A offers to concede his opponent's (Golfer B's) putt if Golfer B reciprocates by conceding Golfer A's own putt.
In match play (not stroke play), golfers have the option of conceding an opponent's putt. For example: Golfer A has already made her par putt and her opponent has a 2-foot putt left for par. Golfer A can concede that putt (Golfer B picks up the ball and moves on, counting the putt as made even though the ball wasn't holed). (It is also acceptable under the Rules of Golf for Golfer B to request that Golfer A concede that putt, but it is solely up to Golfer A whether or not to do so.)
In the rulebook, concessions are legal only in match play, never in stroke play. Since "good-good" is a quid pro quo involving concessions — "I'll concede your putt if you concede mine" — it is also only allowed under the rules during match play.
So let's say you are facing a putt that you'd really rather not have to make, while your opponent also has a testing putt remaining. "Good-good?" you ask your opponent. If the opponent replies in the affirmative, you both pick up your balls and move on to the next hole, counting those putts as made. (If your opponent declines, sorry, you have to putt the ball.)
So what "good-good" boils down to is this: "I'll give you your putt if you give me mine." Note that agreeing to concede one another's putts is only allowed under the rules during the play of a given hole. Two opponents agreeing before the start of a match that they will both concede all short putts (or any other types of putts) is not permitted.
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