I don't think it's an ad hominem attack. What I've said is true. Just because someone is passionate and interested in medicine in their free time doesn't qualify them as a physician and the same is true in this case. It is possible that Scott Adams will end up being correct, but there are other people that have devoted a lot more time and energy in their lives learning and researching this subject than him, and I would prefer to spend my limited time listening to them instead. I think they are much more likely to be correct.