But the point is to assume
that the force pushing them back is larger!
If you don't assume that Phillips is right then you can't test any of his situations. He claims that by relaxing you can project the attacker's force back to them, so when he pushes he claims that his arm strength is not the major factor. We have to assume that he's right if we are to analyze any of the scenarios.
Well, this may be a language issue...but if not, I certainly hope you're kidding.
Assume nothing. Trust no one. Test everything
From that video, here what we see: one guy pushes a little, the other guy moves a lot. Ok. Question: if we discount the impossible...like a wizard did it, or some kind of mysterious Obi-wan esque Force Push (damn that would be cool), what are the likely possible explanations? Then, we can work our way through those, one by one, until we get enough info to form a opinion.
Mr Phillips claims he's not 'just pushing against the ground'; ok, if that's true, then if we were to remove 'the ground' (sitting on a chair doesn't remove the ground), he should still send those guys careening across the screen - right? Else...what he's saying and what's he's doing aren't the same thing
Or - if something takes X amount of force to move...it takes X amount of force to move. Ok. So...if you're going to say 'I can do Z'...well... Z has to generate X amount of force.