The Head-Fi forum does have a useful purpose. If you are, for example, looking for a headphone, it is very useful. You can, with some degree of reliability, pick a headphone to try based on tonal balance comparison to another headphone for which you are familiar, if you base this on a large sample number of user opinions to gain some level of statistical value. However, only rely on tonal balance vs. a known reference. Never rely on any absolute determination by most users; the are primarily without a clue. For example, this would be a useful type of statement(if shared by a large number of users): "X headphone has what seems to be a higher level of low bass as compared to headphone Y."
But most of the stuff discussed on that forum appears to me to be useless, and quite often, fictitious.
I do go to some of the bigger physical headphone meetings, however, as a matter of relaxation. I do not argue or attempt to correct these people at meetings; I go for recreational purposes, and to listen to the latest high-end headphones.
-Chris