Alternative way to loop underspin

I can see the differences and to make it crystal clear:

1.  These differences are built into how they loop any ball, including their basic loop vs block.

2. Their modifications for underspin are similar when their basic loop is understood.

If you look at Harimoto, Boll or Ma, all these things you are pointing out are in their basic loops.

I will leave the issues with your inability to understand my sarcasm and issues with arthritis for another time.

Actually to clarify when I was talking about the direction of the feet, it was relative to the hitting direction rather than the table. Relative to table is hard to say because there's many possibilities. But feet position relative to the hitting direction is usually quite consistent for any player. 

Yours looks pretty similar to Harimoto's position except for the extra thoracic rotation that he has and he rotates a bit more on the nonplaying foot. 

I would tend to go as efficient as possible, gaining little things here and there is what pays off overtime. Think of cyclists selling their mom to shave 20 grams off their bike. I bet those guys at the top of TT are the same, if they can get an edge, they'll work for it. The only thing that strikes me is the brutality of his fh, the legs work in the backswing and the swing is so strong, stronger than needed, the same racket speed at contact can be reached spending way less energy. Compare throwing a disc and a sledgehammer, it seems he throws the latter. But there is maybe a reason for that, if fluidity builds up on top of that as he peaks a couple years down the road, it could be scary for example.

As an aside, that is why I disagree with Blahness's claim that Harimoto's backswing is "way too much arm backswing." At best it's ambiguous or misleading because the ML video clearly shows ML taking a very long arm swing-path against backspin. Harimoto's swing-path is just as long except the arm is a tad further from his body.