You already know what my stance is. I don't support ANY broken, flawed, ineffective, defective, incomplete, confusing language for ANY reason.
I am not at all convinced by it. I'm deaf and I've never had any form of so-called "Signing Morphemes" when learning English so I guess I can certifiably conclude that this method is clearly an epic fail. I fail to understand why must hearing people continue to develop more and more complex tools to help deaf people to learn English when BiBi (ASL and English) method is a proven method.
Look at Grendel and FJ and their daughters. It clearly worked for them just fine. Don't you think it raises any concern if there are dozens of methods to help deaf people to learn English especially since these methods are not widely used?