As I recall from my military days long ago: spread out, one gernade will get you all.
Surely on a dynamic entry, the whole squad is not going through the door en masse either.
2man initiates (bumps, pats, squeezes, yells whatever), or the breecher breeches, 1man enters and everyone floods in clearing out of the way of "the fatal funnel"....ie the doorway where all the enemy fire is going to be concentrated on.
Now, so far as the maneuvers through the door plane......I leave that for perp#2 to find out on his own.
The idea is to get as much whoopass into the room as quickly as possible while clearing the fatal funnel. This is to clear the corners so your 1man doesn't get shot from the side. The defender is on home turf in a room and the odds (if he's trained) are in his favor. En masse is the only way to do it.