"Note that on any forum the posters there are biased to a fault. They would not be there if they were not. If one is convinced of the value of a particular stock you invest in it. That automatically biases you to that stock, it is only natural."

Agree that it's natural. However, one would hope that even someone biased toward a stock could and would be courteous to those expressing opposite views in respectful ways. These message boards generally dash those hopes of civility and more normal discourse.

Haven't most investors been wrong enough times to realize that's a real possibility yet again?