The best single rule I have found, useful for academic disciplines as well as internet forums is "Everybody overstates the accuracy, applicability, universality, precision, or other some other aspects of claims they have made." Anybody who actually cares enough about something to go through the trouble of writing it up, unless they are being paid by the word (which has been noted elsewhere has its own problems), is going to be emotionally invested in their work and writings. So my best advice is to assume from the beginning that it is overstated, and consider a weaker version, or a charitable interpretation, of their claims.

Given the limited amount of information available in an online post, a charitable interpretation is even more warranted online than in a book.