Sorry. I was just kidding around a bit. Don't take me seriously. Hand balancing is learning to do handstands...it's supposed to be good for the core...if it's any good in developing IP/Aiki, I don't know.
PS Thanks Chris...
Cartwheels used to be a standard part of the warm-ups at Katsuyuki Kondo's dojo, it was hell until I got used to them.