As somebody who spent a lot of time in the B&W darkroom 50+ years ago, I often find it helpful to temporarily enable the monochome module before adjusting exposure, and assess the picture from there.
I question whether this could be taken a step further by using the colour picker to assess where known midtones sit. For example, a grey card sat amongst correctly exposed mid-tones, would have a monochrome RGB value of 127 127 127. IIRC under the same lighting, untanned Caucasian skin would be approx 153 153 153. Given that our eyes deceive us but our pictures are likely to include a suitable person, could colour picking be a way to appease those looking for a scientific way forward?