There is no down side to trying this except financial for most people. I think given that, if someone wants to try it, they should. I just have not in ten years come across someone that has had a reversal of acute dry mouth via this process. There have certainly been a lot of researchers who have looked at it, and of course there is no shortage of people selling the idea to others, for reasons financial. It's a buyer beware and your milage may vary kind of thing. Just go into it with an open mind I suppose if you wish to try it.
There are means to actually measure salivary output, and if you were going to do one of the studies (like the one at MDACC) they will actually measure you before and after to get hard metrics on effectiveness.