Probably the most common condemnation of open carry comes from the armchair tacticians who believe it’s better to have the element of surprise in a criminal encounter.
This is what I've noticed as well. From other forums that I frequent, its usually CCW advocates who come up with 'what if' scenarios and are against open carry.
In my state (WI), open carry has been leagl for a long time, but noone practices it due to the fact that the majority of the Chief LEOs in different areas have the atitude that a person seen openly carrying will be immediately put to the ground and charged with disorderly conduct (mumbles something about 'upholding the constitution' *spit*). The open carry movement has picked up a lot of steam in my state recently because of the favorable outcomes of a few court cases where a few men who have balls bigger than my head went about their business openly carrying, were arrested, charged, fought their cases in court, and won.