If your tone mapper (filmic , sigmoid ) is not turned on, then you’ll see clipping (i.e., in the histograms in the Color Balance RGB), which is corrected later. So no point in worrying about the histogram at this point.
Earlier the day yesterday I used Color Balance RGB first, made sure the histogram didn’t show any clipping as I adjusted the sliders. Then I used Sigmoid.
Steven yesterday suggested trying the reverse: Sigmoid first, Color Balance RGB after.
Indeed, when I did that, I found the histogram in Color Balance RGB was less material as the Sigmoid had already compressed the range and limited chances of clipping in the former. Similarly, I found after use of Sigmoid my use of Local Contrast was largely unnecessary as the former, in globally adjusting the tone also adjusted the local contrast.
So, I now understand better what Istvan, Steven, Todd, Miguel and others said in response to my Qs. I guess I’m graduating from kindergarten, ready for elementary school, and excited about it!