The only game footage I've seen of what I suppose to be Marshall mechanics in action is what looks to be a highly edited video of Mike Farrenkopf pitching against some hitters.
Highly edited....meaning that there are are only a few ABs represented, and the overall result of each AB is usually not shown (there are a couple of strike 3 pitches--these are definitely featured prominently) but...
...in fact no balls, wild pitches, hit batters, hits, walks, or balks are shown. If the video clip fully represents his entire collection of "good" pitches from a whole summer of pitching (I think this may have taken place in Colorado one or two summers ago), then he is probably just delusional. I understood the "fat old guys" comment someone else made in this thread when I watched the Farrenkopf YouTube video--most of the hitters he faced looked like bottom-of-the-barrel washouts to me.
The other available video is just the usual Marshall stuff: A bunch of guys throwing into nets or to a catcher in Zephyrhills, or the "Amazing 12 Year Old" throwing to his dad in his backyard.
These guys look horrible--their vast collection of pitches, with impressive-sounding technical names like MaxLine True Screwball, don't appear to have more or better movement than anybody else's pitches. The Amazing 12 Year Old does not have amazing velocity, because his father has gunned and reported his fastball: 50 - 55 mph. For a 12 yo, that is a very average, if not slightly below average, range. He also doesn't throw with any kind of control, if the clips his father puts up on the internet are any indication. Since they are presumably his best...that's not too good. The Amazin' is also seriously at risk to take a line-drive comebacker to the head if he ever pitches competitively--he ends up with his face turned somewhere between 1st base and 2nd base--he would likely not see a line drive to his head until it was too late to react properly.
The older jokers whose video is posted on Marshall's website will not suffer any pitching-related injuries at5 all because they will never pitch at a competitive level. In particular, Jeff Sparks, who was clocked in the low 90's when he pitched for Tampa Bay with traditional mechanics could not break the mid-70's when he pitched from a mound at ASMI with full-Marshall mechanics. Wow. Neither could Joe Williams break the mid-70's in ASMI's study of Marshall pitchers, even though he goes by the optimistic pseudonym of Fastbal95.
The old Marshall guys, will never play becuase they are no good (Sparks and Williams, for instance were both released a year or two ago from an indie semi-pro team--during spring training!). They were only there in the first place because manager Tommy John is a friend of Marshall's (or, was...Marshall let him have it, too) and he promised them a try-out. But, they were so terrible they couldn't make the Bridegport BlueFish, and there it is...
Even worse, Fleisig's ASMI study concluded that Marshall's pitching motion actually incurred more stress to the elbow and shoulder than the traditional pitching motion, while drastically limiting Marshall pitchers' velocity. Nice... a real lose-lose situation. But, predictably, it is not Marshall who is wrong, it is everyone else. Flesig, who has 70+ peer-reviewed biomechanics research articles to his name, and has an international reputation for conducting careful and properly controlled scientific research is now "diss'ed and dismissed" by Marshall and the rest of his voodoo cult,i.e, "Fleisig is a moron and he destroys pitching arms".