I think u r exaggerating a little cause believe me when i tell you that placing equipment controls spawns. Try it!! Place a sentry, ims, or whatever in a known spawn point on map and leave area. I promise u will not get a hit marker or kill from that equipment. The best spot would be the corner below stairs to hot dog stand on Strikezone. We do it every game!!! Thats the only way to hold that side of map.
And domination has always been about spawn trapping. lol Thats how u win!