How to draw light and color for color & light to realism (JP Oversized)

Gurney's approach emphasizes realism; I'm curious what motivated the shift or expansion in this second volume.

Some techniques felt advanced, and I wondered if beginners might need more foundational guidance or if it's suitable for all skill levels.

The book seems to straddle art and science — I wonder how he recommends integrating personal style within the realistic framework.