And we all know that a stalinist mappers worst enemy is the grammer (and spelling) nazi.
Are you setting a trap or are you just easy bait?
As for walls: One one side various mapping aspects like water, buildings, fences and walls are obstacles which can control/influence the flow of gameplay. On the other hand, their implementation also has to do with the suspension of disbelief. If people for whatever start to question the "game logic" behind a certain aspect the suspension of disbelief is threatend.
Walls are one one hand an easy/simple thing to block a path off, on the other hand it sometimes doesn't make sense. Same with say, rivers/water, in many games you can either not cross the water at all, or if you can the change is often huge as there are few limintations: soldiers can swim across and are ready to fight instantly. Their isn't any consequence after crossing the river: not being able to get all gear across, haivng to keep gear dry, being wet, cold perhaps. The less simple (more complex) a game becomes, the more people will start to expect as the game becomes "more real" , people will be more liely to use "real logic" rather then "game logic". A solution? More complex engines that can allow for more "real" gameplay; walls that can be destroyed by heavy vehicles like tanks in a convincing manner while still "blocking" smaller vehicles and infantry. Obviously the final choice really depends on the game developers and which gameplay logic they are aiming at, and once that's set it should be as consistent as possible.
Hmm thinking of it, the old logic of "anything that sticks out the ground will block anything dead in it's tracks, tanks are stopped by 1cm thick poles" went overboard when you could pass fencings and such. This new logic makes people wonder about other logics in the game.
Having set al that, I am happy with tanks nothing being stopped by a silly poorly constructed wooden fence.