A sniper of any skill stature could easily keep his dot right there, on that door, and suppress the whole enemy team. 2 snipers with huge concentration, you got a problem. Any mapper knows how horrible, stressful, and deadly leaks are. If you don't know what a leak is, let me explain it for you. Consider this void as a poisonous gas.
Leaks easily happen without micromanagement, and even with that, they still occur.
Well a very important part of the compiling process of a map, VIS, will not run. The smallest of rooms you cannot see the other side. This drastically affects gameplay in any of maps. And this map has a leak. This is a problem, just as bad as respawn camping.