@bluc The question from op was
How would one approach selecting (varying) degrees of shadows and desaturating them?
Then you asked: How do you think to desaturate the shadows or to saturate the highlights?
Please excuse I gave an answer 
@bluc The question from op was
How would one approach selecting (varying) degrees of shadows and desaturating them?
Then you asked: How do you think to desaturate the shadows or to saturate the highlights?
Please excuse I gave an answer