This is an excellent book, but what makes it so relevant to WS oils is the fact the Mr. Weber uses Holbein Duo oils exclusively. The book is written for all oil users, but Mr. Weber gives tips about WS oils in every chapter. For example, brush cleaning. He says to just dip the brush in water and move the brush around on the palette. That way, he says, the brush does not become gummy from too much water. Wipe and repeat. Great tip!