Some hands are just dogs. However you play them, you're going to take more points than you'd like. Other hands get close to giving you the tools to shoot the moon, but fall a few points short -- missing the Ace of Hearts, or something like that. Going for the shoot because you're behind on points, trying not to take any points when you've got an awful hand and ending up with nothing but Aces and Kings for the last four tricks, all of these things are recipes for disaster.

Play the hand you have. Take eight points or fifteen; if you play your hands right, on average, you'll end up ahead. Remember that everyone has a few dogs in any reasonably large distribution of hands, and that your opponents will get stuck with equally bad cards equally often. Accept the hand you have, get a fair outcome, and move on to the next one -- the one you can take 0 points with, or 26.