[Retric]

Why is it OK to lump honest physicians, researchers and patients in with snake oil salesmen and their victims?

The best snake oil salesmen believe in their products. There are already exceptions for allowing people to take highly experimental procedures when there likely to die without them. However, there are plenty of cases where highly trained well meaning doctors caused massive suffering without benefit to their direct patents.

As a recent example of fringe medicine, a few athletes have injected themselves with stem cells. Not to mention the modern version of doping which often involves substances that are known to be harmful or medicine has little idea what the long term effects are.

[maxharris]

So we should treat every physician, researcher and patient as guilty, incorrect or foolish until proven innocent, correct or wise?

However, there are plenty of cases where highly trained well meaning doctors caused massive suffering without benefit to their direct patents.

No one is omniscient. The ideal in medicine can't be something impossible (i.e., medicine that cures all ills and everyone, and never has any risks or side effects). No one knows how to do that (now and for the foreseeable future), and we shouldn't deny people the best chance they have at life to chase an impossibility.

[Retric]

So we should treat ... researcher... as guilty, incorrect or foolish until proven innocent, correct or wise?

Yes, that's the point of peer review.

[maxharris]

Peer review is just another thing that helps individuals decide scientific matters for themselves.

The implicit idea behind peer review can be summed up like this: "This is what I think about this work. (I have credentials X, Y, and Z, and I've published this stuff you many have heard of.) What I have to say is just another thing for you to consider. Take it or leave it."

[Retric]

It's more than that as it's vary possible for things to fail peer review and or be edited and resubmitted. But, also in some ways less as you as a reader don't know who did the peer review.