Rigor Mortis: fair question. The book has a new warm up routine that makes more sense than the one in ETK, in my opinion. The section on breathing is brand new, so far as I can tell, and has some great drills.
If you are looking for groundbreaking material, this is not it. This is a simplified, streamlined presentation of the Program Minimum which strips out all unnecessary variables. Think of it as an update to ETK's PM. There is new material, but certainly not a new approach.
I have ETK, RCK, and ROTK. This book is worth the $10 price tag.