Quote Originally Posted by waldronate View Post
Because I'm too lazy to actually try this, how does this technique compare with using a single multiply blend mode for the grayscale modifier on the color?
Using a single Multiply ends up darkening the overall colors too much. This method allows you to preserve the base colors while just darkening the shadows and lightening the highlights. If you watch the video, it shows both methods. Multiply works for a fast and dirty shaded relief, but this method allows for a lot more control.