What I mean is that there is a very big difference in the game between a player having a lead figure on a map which shows a small stream and three boulders and six goblins standing on the otherside of the stream 8" away, and the GM describing the situation.
If the GM has to "describe" it, rather than just letting the players look at the tactical situation on the map, this leads to more descriptive role-playing on the player's part because they are not just moving their lead figures, they are decribing what they are doing to the GM.
"You come into the clearing and you see 6 goblins on the otherside of a small ditched stream. The goblins are about 50 feet away from you but apparently have not seen you yet. There are three fairly large boulders, two on the goblin's side of the stream and one on your side of the stream. The boulder on your side of the stream is about 20 feet away from you. The boulders apprear to be large enough to hide 3 people behind, but it will be cramped. Two would be better."
That adds much more flavor than the ranger moving his lead figure on the board up to the boulder and say: "I'll use the rest of my move to draw my bow."
It does to me anyway. YMMV.