You claim that the practice of grounding while being pushed cannot be found in modern Aikido. This is a strange claim to make. It is a regular part of training in most Ki Society schools and I have experienced this training in both ASU and USAF, and at seminars with instructors from other organizations. What exactly is your point anyway?
A number of ASU folks have had contact with Dan Harden and some have hosted him in their dojo. Why don't you just check with them to get your answers and to determine if he knows his stuff, as well as teach it. If you are not going to make the effort to check it out in person maybe the word of someone you have trained with and respect would either clear the air for you or give substance to your concerns.