For this subject, it's really just a matter of opinion more than anything. I think if someone is commenting and has subject matter expertise, they should menti

For this subject, it's really just a matter of opinion more than anything. I think if someone is commenting and has subject matter expertise, they should mention that ("I'm a doctor and happen to know that ..."), it's better than having everyone else adding disclaimers to their comments. In an online comment no expertise is usually assumed, but yes this leads to stuff like a scientist with decades of experience publishing a study saying something that people don't want to hear, and then some troll on twitter says "No it's not" and people run with it because that's what they want to hear. I think it's the Internet in general, it's not specific of HN.