In Boyce's defense, I am not sure he falls into the category of "charlatan." It's interesting that you mention the LAP because there was an older woman in my class getting a LAP revision to a sleeve. She asked what surgery I was getting and when I told her she said "Oh, that's the big one!" and then said "At my age, I'm not looking to lose much more. I just don't want to gain and the Lapband is making trouble for me. But that big one, if I was your age, that's what I'd get." Her husband chimed in with "She's had the Lapband in her for almost 15 years and we didn't know it was supposed to come out after a while." I didn't get a chance to ask if Boyce did her original lapband, but I got the feeling he didn't since she said "When I went to Dr. Boyce I thought I might need a fill to fix the problems with swallowing I'm having but he said no, it's overdue to be removed."
I think he really does believe his program is comprehensive and resolves all the nutrition issues. It's like one of those things that when you get too close to the issue you can't see the problems with objectivity any longer. I think he doesn't see the NUT issues for DSers with objectivity because he is so invested in solving the problems that he cannot see the points he is missing. As a researcher myself, I appreciate that he's so invested in making sure research backs his surgical decisions and part of the problem with DS nutrition advocacy (and Vets, please correct me if I am wrong) is that there is actually so little real hard research. We have certain voices, like Dr. K who emerge and publish and a few other published findings that support what the vets all already know from living DS, but that is pretty much it. Someone (I cannot remember who) had mentioned in the FB DS group something along the lines of "Would surgeon's believe the NUT issues if it they were published by DS veterans?"
It's actually not a bad idea. It may be time for DSers to compile qualitative research on nutritional deficiencies and join forces to compile labs. I mean, hell, we are actually in a better position to gather that material than so many of the surgeons who, outside of a blind study, only ever see the labs of their own patients.