Not spamish at all. In fact you are asking all the right questions. The simplistic and disengenuous views of the Wegnerites would be that all the guys you mention have nothing to contribute and have destroyed American tennis because they don't agree with Wegner--or even take him and the disciple/worshippers seriously.
It's just that it would be a life's work to answer those questions--oh wait that's why I created Tennisplayer.net... literally my goal was to learn everything I possibly could from everyone I could find who had real credibility. There are now articles from over 50 coaches and many extended series outlining what and how they teach.
My other goal was to create something else that had never existed: a video archive where anyone could study all the top players for themselves in high speed video--and not these horrible utube practice clips without frame by frame advance, but strokes in live match play with high frame rates, high resolution, clips that you could advance yourself one frame (or more) at a time... There are about 65 top players there.
I made the offer to a few people before and suggest you take me up on it to look at the site for a week n/c. Virtually everyone you mentioned and many many more have done extended article series on what they teach.
If you educate yourself more you can answer some of those questions for yourself--which is the only way it really works.
email me at: email@example.com
And I will follow through with you other guys who made the request. Just been swamped. Anyone else that wants to jump in can as well.