Defensive Honors

Under Declarer Play, I have stated that honors are the backbone of almost any hand. Under Defense, I wouldn't make quite so sweeping a statement, given that a low ruff will not too rarely be the ticket to defeating a powerhouse held by the opposition as well as the damage uppercuts can effect with relatively modest spot cards, not to mention the fact that on defense, you're traditionally going for far fewer tricks to achieve a good score than declarers are committed to finding. Nevertheless, if I would postulate a slightly greater percentage of defensive successes eminating from low cards, I would still say honors are the sturdy backbone of the defensive hands also. And you're indifferent to their value at your great cost.
And when it comes to defensive honors, the watchword that comes foremost to mind is that you want to get something with your honors. This commonplace principle indeed underlies the commonly heard Cover and Honor with an Honor, Second Hand Low and whatever value lies behind Never Lead from a King (which is discussed elsewhere). You wanna do something with that honor -- if possible. To be sure, where declarer sees all his 26 cards, the defense sees only half of theirs and can't always sort out the effectiveness of their honors. The good news is that the people you're competing against have the same problems and your goal should not be something approaching perfection but making fewer mistakes than those other guys.
So you're not asked to never, never let slip an opportunity to use your honors productively, but to watch carefully and get something with your honors when you can -- more often than those other guys.
You'll find links to some illustrations of careless disregard of the value of honors here.