Sadly I don't think your can has any worms in it...
I would argue that Jay Green is credited in the appropriate place - the historical record (eg. Wikipedia). He was one of a long line of people who made innovations that improved on a piece of equipment that is now standard to the artform. It might be nice if more people knew about his contribution, but how many pianists know everyone who contributed to the development of their instrument?
Is there an ethical question regarding the use of acrylics? Using acrylic as a robust replacement for glass is not a juggling innovation, so it seems absurd for any juggler to claim ownership on this.
[I apologize if I'm just re-stating arguments from the thread you mentioned - I detest Facebook, so I have not been following it].
Regarding individual moves, I have a suggestion - let's follow the naming convention used in gymnastics. Henceforth 5-club-backcrosses shall be known as Kisses! eg. "He did 30 Kisses in a row" or "Her Kisses are amazing"
And of course, under this convention, we can say that anyone doing contact ball moves is "just going through the Moschens" (sorry, couldn't help myself)
On a slightly more serious note, if you want an example of what happens when you start crediting people for every refinement/adaptation on a particular move/trick, look into modern close-up magic instructional vids - it can be taken to ridiculous levels.
What Michael Moschen has achieved goes beyond an individual move or technique, he has expanded the artform into new territory - not just with contact juggling, but also with his work with abstract shapes (I would argue). Does he now "own" this new territory? No, in the same way Picasso doesn't own cubism, or Martha Graham modern dance. But all of these individuals are rightly credited with taking their artform into completely new territory - genuinely expanding their artform, how many people can claim that!?
On the other hand, of course Mr MM owns the works he has created. To copy his triangle piece without permission is clearly unethical, in the same way that dancing a Martha Graham piece without permission would be, and to copy it poorly is just plain unforgivable. To my mind St Jules shall henceforth be regarded as a carbuncle on the collective bottom of the circus fraternity!
Thank you for your provocative question, I have been thinking about this all day, and looking up Martha Graham led me to an amazing quote (which I'll post separately so as not to overload the thread).