I think you refuted them very well just now. You simply discussed the issues without the emotions, or casting the opposite opinion in rather negative terms to start.
Let's be clear...I am an outsider looking in. I have no experience with Endo Shihan, and little experience with this style (Yamaguchi Shihan) of training. I have done some locally, and have had the priviledge of some contact with 5-6th dans. And I really enjoyed that training. But the things Mr. S. has mentioned also seemed to be present even in the environments I was exposed to.
I really don't have a dog in this fight...I'm just asking questions, and thinking. And I appreciate the conversation, so I don't mean to cast it negatively either. Thanks for tolerating this YoshOrc (TM)...
PS I should perhaps correct myself...the local group from that tradition NEVER talks on the mat. They just sweat!