Winner-Enablers
Top honors are (by and large) recognized for their value by neophytes and experts alike, while more experienced players will keep a sharp eye out for those occasions where lower honors along with 9's and 8's, perhaps even lower cards, become important on a hand. But there's another kind of valuable card, one that has no chance of winning a trick, but can be the only means by which another card becomes a winner, unsung heroes, as it were.
I have chosen to call them winner-enablers. Yes, I would agree that it's a yukky term with too many syllables and I could wish that the concept had given rise to a short and snappy word like stiff and , and indeed might even suggest that had it done so, that snappy term might have generated more widespread recognition of such cards. Well, anyway, for want of a better term, which at least has the saving grace of describing the function of such cards, that's the term I am using.
These appear in three forms, to wit: (1) failure to get an obvious ruff in the short hand, thus increasing trump winners; (2) discarding cards (often to avoid a finesse) that would have promoted a winner in that suit; and (3) playing too high a card (often an apparent signal) on defense.
Below are illustrations of cases where winner-enablers were overlooked at a cost:
Trump
High Cards
Defense