I don't know how much of the video is legit, but don't you think that there's a high chance that pros do a lot of special things subconsciously, so small that you might not even see them?
I am absolutely convinced that the better the player, the better his micro adjustment is.
But in this video micro adjustment is defined as muscle relaxation before the stroke.
For me I would understand micro adjustment in the way that you adopt your stroke to the incoming ball.
yes its true
for example have you seen how pros adjust their grip when serving? they let the bottom three fingers go to get more wrist which means more spin. That could be considered a micro adjustment