What wrong information? The fact that a few aquarists have successfully kept more than two clowns in the same system for many years doesn't mean that the naysayers here are giving wrong information when they say that this is a plan that generally doesn't work out in the long run. It just means that those people are the exception to the rule.
When information appears not just in online forums, but also in magazines, books, and other professional literature, I think it's likely to be fairly reliable. That doesn't mean that, in spite of conventional wisdom, some people haven't successfully kept more than two clowns together, or trained orangespotted filefish to eat prepared foods, or kept multiple species of angelfishes in the same system (etc.). However, it does mean that these people are either exceptionally dedicated or exceptionally lucky, or both. Informing new aquarists of this is doing both them and the animals they're planning to keep a favor. I agree that a blanket "no" may not be helpful, but for the most part, what I've seen in these threads is experienced posters saying that it usually doesn't work. That's not a blanket statement.
As far as the second comment goes, I don't know how you'd make that distinction obvious, unless the moderators started requiring everyone to post a sig file detailing how long they've kept SW aquaria and which animals they've kept. I suspect that posters who dismiss as biased and/or anecdotal any advice or experience that contradicts what they want to do are really just looking for endorsement, not advice. And that's their prerogative, naturally.
