I shoot with a marine who served in Iraq. The training that they received was for the marine on point to have his rifle on "fire" and the others behind him to have it on "safe". Once they moved into a building, if a soldier's rifle moved to his shoulder, he flicked the safety off in the process. Also, if they were stacked up to clear a room inside, again only the first soldier would have his rifle on fire before entering. The first three soldiers stacked up would clear the room, but only the point man would already have his rifle on fire upon entering.
My friend said that training helped immensely with how to clear a house safely and effectively. But, as always, some improvisations were necessary.