Clipping masks, color fills (without masks)

The colors (red, yellow, blue, green) are color fills with their masks deleted. Then they're set as Clipping Masks so the "hue" smart object below them inherits the selected color.

Toggling the visibility of the color fills toggles the grid of colors on the left. Which makes it pretty handy for trying the feel of different colors. I could see this same "Color fill + Clipping mask" approach working nicely for applying a primary/secondary color scheme to a variety of elements on a single page. Hm, neat.