Lets say, for instance, the party is battling trolls. One of the players, in the midst of combat, wishes to light a torch and start burning troll bits to stop a defeated troll from regenerating back up into the fray. In a "DM vs. Players" scenario, the DM would most likely be inclined to favor getting "his" troll back into action to whup up on the PCs some more, and tell the player its going to take a couple of rounds to light the torch, a couple more rounds to effectively burn troll bits, and all the while suffering the undefended attacks by the remaining trolls.Read that again. While it might be tempting to squash that irritating player, god knows I have done it myself!, it is really crucial not to.
Unfortunately, what this DM is actually doing is punishing creative play. "Get back to unimaginatively rolling 'to hit' and damage", he might as well say, "or you're going to get pounded on."
That's some really good advice there for how to be a better DM/GM/whatever.