I was thinking of a maul, yeah. What I've spotted is NFL guys pushing with their hands on a teammate's back, instead of (like in rugby, or what the Eagles do) g

I was thinking of a maul, yeah. What I've spotted is NFL guys pushing with their hands on a teammate's back, instead of (like in rugby, or what the Eagles do) getting their shoulders against his ass or upper thighs, which gives more power and better leverage. Good point about using different players, and I even think I've seen that a time or two. As for why not always do it, I'm only guessing, but there may be an inherent advantage in preserving the possibility that it won't be a "tush push" play (I mean, maybe not for the Eagles, because they're so good at it, but for other teams who aren't). Like, maybe it keeps the linebackers a step or two deeper and increases the likelihood of success; or, if they provoke a "tush push" defense that opens up a more-promising play then the QB is best placed to run the counter. I don't really know, though.