You cannot learn how to play guitar if the guitar is out of tune. No matter how well you play chords or notes, it will sound right.
However, if you can learn to tune the guitar then you will have a better understanding of how you can produce the emotional quality of what's inside you.
The same is true about understanding color and value and how they relate to the source intensity and overall effect of light. If you can develop an understanding of that then the rest is be technical execution.
On cloudy days when the sun's intensity is fluxuating between full light to diffused light, all the colors I see change back and forth with equality to one another.
The effects are incredible.
The temperatures change from warm to cold to warm again. Shadows appear and disappear. The contrast, colors and values change. But, to me there is a principle at work that is measurable and understandable in it's principality. It's unified no matter what the mood.
Seek to master this and the source of that emotional intensity and effect will ultimately be a shared interaction between the artist, the subject and the viewer.