so which is it? i believe you're saying it can't be determined either way despite the extensive research on both ends (but you're using way more words). i also think you are an open carry proponent, which is fine, but i won't try to argue my point to you citing people and books, etc.
you might be right, maybe visible guns do deter crime. i still refuse to hang my pistol out for everyone to see when i am in marsh getting a gallon of milk or at hooters eating some wings.
Actually, what I'm saying is that while there isn't conclusive "proof", what evidence does exist all leans one way.
On the one hand, we've got two cases--ever--cited (Ayoob's) where maybe someone was targeted first because they were openly armed. On the other, we have from several tens of thousands to more than 2 million instances annually of cases where the bad guy was dissuaded from committing a crime when he became aware that a victim or 3rd party was armed.
The specific case--OC "crimes avoided" vs. OC specially targeted, has not been studied. (Frankly, it would be a difficult and expensive study to set up, particulary if one is looking for anything close to a definitive "answer.") But a lot of related things all point in one direction, suggesting what the results of such a study would likely be.