The CAT handstand is great. I love the detail of the weight being transferred into the arms and shoulders when the legs lift off the ground, and your website is fascinating! What an interesting fellow you are! :)
You are using CAT in the example above then, which I am just getting into. How does it compare to automatron and other systems you have used? I don't have much experience with character rigging, but CAT seems to work quite well out of the box with just a few tweaks here and there which aren't difficult to do.
Doug.