Texan makes some very valid observations which I think many of us would do well to heed.
I know that in the past, I have posted a sensitive question on behalf of a friend and at times I have posed questions under someone else's name. In doing so, my purpose was not to hide behind an anonymous screen name so I could say ugly things, but to avoid embarassing my son.
Yes, I could have PM'd someone with my question, but in my early days on HSBBW, I did not know any of the posters well enough to either trust them with the information or to trust the validity of their advice. Even now, I occasionally prefer to post a difficult question on the board rather than through a PM so I can get a variety of opinions that help to form a well-reasoned decision.
The only problem I would have with an anonymous poster is if he or she attacked me or my son without reason. A while back, I posted congratulations on a local baseball message board and a smart-aleck kid -- hiding behind a screen name -- called me an f-in _itch. I have no idea what that was all about, but I can assure you it did not elicit positive emotions.