Well, I'm not a scientist. I never went to college. Never took an anatomy class. But to my admittedly uneducated mind, the Loop in the SADI just looks like it would allow the contents to back up the wrong way. The DS is more of a Y configuration, so again, in my (again uneducated) mind, it doesn't look like it would encourage the same action.
I could be wrong. I'm no surgeon. No degrees past high school. But I have excellent common sense, I found the Duodenal Switch without any kind of on-line "forum" input to help me research my options. I looked at things, again with my uneducated mind, and made (I think) an excellent decision. I even saw through my surgeons BS about "paint peeling, room clearing flatulence" and raised my hand and made him clarify how to simply avoid fartogenic foods. But I'm admittedly famous for flunking sex education in high school, when I was painfully too shy to ask questions.
Quite often I am asked my opinion by family and friends when they need someone with a fresh perspective. I have a unique ability to think outside the box, to come up with solutions nobody else thinks of.
A really good instance of this is years ago at a dental conference I attended on Collections. The speaker cornered me at the lunch break after I had asked a question during the morning. She pumped me through the lunch hour on my collection practices, which I found oddly flattering. Imagine my surprise when, in the afternoon session, she ditched her slides and lectured from notes. And presented MY ideas. My office manager was there at the time, and said I should have sent her a bill. Same speaker later included my ideas in software for the dental office she developed.
But again, I'm not college educated. Just a simple person.