Everyone stand on my side of the mob and push!

[Pep]

Sometimes there's a caster mob that can't be interrupted and the only way to stop it from channeling a spell is pushing it plenty. What causes push and how do I maximize it?

1- Does STR make any difference?
2- Do more swings per minute cause more push? Does haste cause more push?
3- Is it the choice of weapons?
4- Do the stun procs of Gnoll Hide Lariats and Sarnak Warhammers cause push, even if the mob is immune to stun? The mesmerize line of spells have both a stun component, and a mesemerize component. I wonder if stuns are also made of two components: in this case a push component and a stun component.

All I know is that everyone has to stand on the same side of the mob to push it effectively, otherwise the sum of pushes tend to cancel out. Also, rooted mobs (and players) cannot be pushed no matter what.

Thanks in advance.