Huh?
What did you not understand from what Jim told you?
He said :
"The waveform display doesn't change with these adjustments".
That means the visual display of the waveforms do not get rewritten when youmake the adjustment.
Reason for this is it is necessary to be able to still see them in case you need to adjust them differently or again. ie. if they dissapeared you would be working on your audio...blind. (so to speak)