”When once we see keenly enough, there is very little difficulty in painting what we see; but, even supposing that this difficulty be still great, I believe that the sight is a more important thing than the painting; and I would rather teach painting that my pupils may learn to love Nature, than teach the looking at Nature that they may learn to paint.”
"Not knowing how to do it is part of knowing how to do it." - Leon Kossoff 
enjoyed the neutral studies. In my fabric design classe the teacher suggested adding a bit of ‘brown’ to give a warm, aged, even antique-‘ish’ tone.
And it bugs me to see blue skies painted straight out of the tube without the slightest neutral nuance. Life is hard when you’re snobby.
I think you have an excellent point about coloring real life straight out of a tube. Neutrals rule, man. Finding the warm vs. cool in them is still hard for me sometimes. I had a “final” today – mixing 3 primaries to match the teacher’s black & white-made grey. Fun! I got a B. LOL.