Welding strategies

I've read there that when making a map you can add weldable doors to a RoomDoorsList to prevent spawns inside a barricaded room.



* Is this put in practice in most maps ? at least stock maps ?



* Is it, in some cases, a viable strategy to barricade entire rooms ?



I've been experimenting in the police station in westlondon with no real success so far, does anyone have a suggestion to which door I should weld to minimize right-side spawns, here's a picture of the area