Root, I understand and agree with, to an extent, your arguments. I will also throw out my small sample of experience and belief and not claim that it proves anything.
A few points of perspective...
My youngest had a wrist injury (not throwing related) that required surgery through the renowned Kerlan-Jobe Sports Med Orthopedic group so we spent more time there than I would have liked. During that time, we spoke to several specialists and PT's that all worked primarily with sports athletes, youth thru pro. They all were consistent with their belief that overuse at a young age and specialization at a young age are key contributors to a growing problem and that there was a direct correlation to the growth of year 'round club and travel ball (of course, along with the bad decisions coaches and parents were making while participating in these events that were contributing further to the problem). Some also went into detail about the physiology of the body and the various stages of maturation. They related some of the overuse issues specifically to younger ages and what the body can withstand at each of those various stages. They are as much the experts as anyone, IMO. Many in this group are active in trying to get awareness out to the baseball community that this is an issue. They seem genuine in trying to use their position of expertise to alleviate the problem. I don't know of any direct financial gain they could see by collaborating on this position as a group.
You made this comment... "When Andrews started seeing more young patients I just don't think it occurred to him that the baseball scene has changed and that those who never would have even thought about scheduling an appointment with him now do." This one, I don't agree with. I suppose it is possible that at one point, this wasn't factored in enough but as much research as he has done and as much as he is considered an expert in the field, I can't imagine that there is not sufficient awareness of this factor. I do agree it absolutely is a factor. I just don't agree that the sports doc experts don't account for it at all.
I have a nephew who has Spinal Muscular Atrophy. Through his early-year struggles, we were immersed in learning about the workings of muscles, tendons, ligaments, bones, etc. of young people and, again, the thing that sticks out as it relates to this conversation is how much the medical experts talked about various stages of development and how the young body, even when completely healthy, cannot handle some of the things a mature body can.
See my earlier post in this thread. Our geographical area is relatively remote by California standards. So, the club/travel scene is still in a growth mode here whereas it has matured quite a bit in the larger metro areas of Calif. I have been part of the coaching scene as well as involved on a broader scope as site director for some of the national youth tournament organizations. I have certainly seen a significant spike in specific arm issues. Is there more participation? Yup. More awareness and likelihood to get any issues checked? Yup. But as that funnel narrows (i.e. - when I get the young players coming into the HS program), it becomes starkly evident that more 8th, 9th and 10th graders are coming in with arm issues already. This wasn't nearly the case when I started working with HS age groups several years ago.
Small sample still? Yes. Does it prove anything? No. Food for thought for your beliefs? ???