Here is a minimal pipeline (image credit: @Tamas_Papp ). No curves, no tone mappers, just white balance (the ‘legacy’ method, only a linear matrix operation), demosaic, exposure:
at 0 EV
at +1 EV.
‘a’ and ‘b’ went from (1.36, 4.23) to (2.70, 8.47) and then to (3.40, 10.67). I even set white balance to the ‘old’ method (no color calibration, only linear matrix operations).