It's for the manufacturer to justify their assertion. Industry in general isn't above designing ridiculous junk and selling it as a disability aid or cure, often at an inflated price. An interesting consequence is that made-for-gaming hardware can be cheaper and more useful to us cripples than purpose-designed aids are.
My own experience of RSI - not carpal tunnel, I don't know what it is really but if I use a keyboard then my forearms hurt with a burning pain for a couple of days, or if I do more then worse happens, I'm tapping this with a stylus on touchscreen and the FITALY software - my experience, I say, is that rapid frequent control actions are bad (and often unavoidable), and a device that lets you perform the same action with less effort, and in more than one way, is good. I'm not sure how this one rates, but if you can also perform fine movement by rocking INSTEAD of moving the mouse, that seems worth trying. But changing to a completely different pointing technology is liable to be better.