re: "What was the purpose of adding this? What relevance is there in doing something like this?"
---------Those are fair questions. I believe that the fundamental basis of Chris O'Leary's pitching mechanics advice is always important to understand within the context of threads where he offers it.
In various forums over the years, including his own website, Mr. O'Leary fervently advocates Mike Marshall's mechanics. On the other hand, he has started to occasionally post that "He has recently distanced himself from Marshall". However, many of Mr. O'Leary's current ideas, in his own writing, clearly still do reflect Marshall's garbled teachings about pronation, "pushing off", etc.
To me this is highly chameleon-like behavior, at best. People that take advice like Chris's seriously... should certainly have the opportunity to look at the basis behind it.
If it is demeaning to post a link to Chris's video clip, demonstrating a pitching motion that he advocates, or has advocated recently, on a pitching forum where people should be able to make up their own minds about it--well,...that's not really a problem that I created for him.