Yes, depressions protect unsightly buildup by their position of standing down.
Quite the opposite of the Tall Poppy Syndrome. https://en.wikipedia.org/wiki/Tall_poppy_syndrome
I would think that sudden reversals of weighted abrasion would exert maximum "torque" to the target surface, exceeding any swing machine.
The ads do not even IMPLY wet (chemical) use.
Wet operations protect the user from asbestos pathologies.
I once used an extremely abrasive black strip pad on a swing machine, dry, and found it did have its positives, but I still had to go back with stripper to get it all.
It was faster that way than using just the wet process.
I was removing about 500 coats of finish that had "set up" over a 20 year period.
Damned near needed a diamond cutter!