Okay, I'll admit to being math-challenged on this (which is why I pursued writing rather than science or engineering— I get the theory of science very well, but the math part leaves my head spinning). But I still got the gist of his point, and am amused that he actually tried to calculate this.
But I think I know why his calculations result in falling times that don't match between Luke and the AT-AT and Hoth's assumed gravitational equivalent to Earth. And that's simply because what was filmed falling was a scale model with an actual height of (I'm guessing) less than a meter. Less height, less time to fall.
But that's unsatisfactory for our imagined premise that this is a *real* AT-AT on a real planet, with a height of 22 meters (give or take).
Now, we could possibly suggest that the reason the AT-AT falls "faster" than it should might be because the blast imparted an additional initial momentum to the fall that makes up the one second difference.
Or maybe Luke just wanted it to fall faster, and with his poor Force control, the fall velocity increased without his being aware of causing it.
Yeah, that'll work.
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