The on-line class, Getting Started in Watercolor is, in large part, exercises to get to know and understand the magical formula of how much water on the paper means how much water and how much pigment on the brush. Its learning what you can accomplish with the different combinations.
In writing about a posted painting a current student, Penny Chapman, wrote:
I have worked on the wet on wet techniques until felt like I was beginning to understand how the water moves […]