As Tapp mentions, map-destruction should have minimal or no overlap with the kinds of "battle scarring" which individual players can cause, so don't preemptively apply bullet-holes or rocket-divots into the ground.
Reminds me that in my artpass contest I
did put some "window cracks" on a particular window that in the valve base had been a solid wall (some other people--like YM--made boarded up windows). I used security glass so that in this odd dead-end location blue could look out towards point B, but not do anything about it (eg. observational view only).
To highlight the solidity of the glass (as to avoid players trying to break it) I dropped two "glass bullet hole" decals on the glass, and by pure accident they're about 3 to 4 times larger than any decal done by bullets
from any player-usable weapon.
So on the one hand, it's a "bullet hole" but on the other, it's HUGE, more like a rock or something big and heavy smacked into the glass (and still only cracked it).
Anyhow, yes.
Decay in TF2 is a very clean style of decay (much like these stairs on my porch where the wood has warped and bent up): no dirt, no scortch marks, no broken bricks, no shattered concrete, no debris, just
age.