In the classic Manny clip you posted in #10, I agree he did not land on a very bent knee, but later in this swing he bent it abt 30 deg (per below) then straightened before contact - maybe it was an off-speed pitch so he delayed the movement, I don't know.
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So, I looked to see what he typically did in his swing and here is what I found in the 1st 3 clips I located. (of course these degree measurements are not exact but they are representative for this purpose)
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Now I know what you consider a very bent knee. Thanks