Hack & Slash has a nice post on DM's preventing players from unknowingly doing something foolish. He ends it with a FAQ explaining why it's not spoonfeeding the players when the DM explains the likely consequences of their character's proposed action. But I think he's missed a point, the communication gap has two sides. While the players perceive the DM's description In their own terms and have only a finite amount of time to ask questions to obtain more information; the converse is also true. The DM cannot see the character's heads turn to examine bushes where the orcs are hiding. So we rely on statements of intent and action to learn what the characters are paying attention to. In response we provide the players with more information, which may cause them to rethink their actions.
I had a good example crop up in the last session I ran. The party entered a large room containing a large number of goblins via a door in the corner. The party's attention was on the goblins, so I described them in detail and only mentioned in passing that there was a curtain covering the end of the room. No one paid attention to the curtain until the M-U was backstabbed through it. When the player announced he had stepped back and was going to torch it with Burning Hands, I provided a detailed description of the tapestry. He subsequently decided not to burn it, instead lifting the bottom with Mage Hand to locate his attacker.
Was I telling him he'd lose a valuable treasure if he went through with his stated action? No, his stated action gave me information about what the character was looking at, which then 'unlocked' more information for the player.
That's the point I wanted to expand on. I fully agree with the post, particularly with the assertion that the communication gap has led to the rise of character skill gaming. The attitude of I don't care what it looks like, what's the skill and DC - let me roll to see if I made it, I believe has taken much of the richness out of the game.