NOPE, WRONG.
Open carry is a good idea. An armed robber is not going to rob a bank if he sees half the customers carrying guns. If they were all concealed, you'd have yourself a shootout.
Now if everyone had one strapped on, thats different. Of course every town would be like the OK Corral with as many irresponsible/hotheads as we have today.
To be realistic, it would be more like maybe one customer out of a group of ten that would have an open carry showing....if that. Even though it would be legal, this isn't the old west. Lets be realistic for a moment:
To beat a criminal, you must think like a criminal.
With that in mind, if I were to rob a bank, upon walking in I would look for anyone who looks like they would ruin my plans. The open carry guy would be imediately picked out as a threat. I would casually ease over in line behind him like any other customer and as soon as he looked forward to await his turn, I'd pull my gun out of my pants and put it against the back of his head and take his gun as a trophy, or even easier, just cap him in the base of the skull and be done with it.
It would be the normal, casual looking customers with a gun concealed about them that would ruin a criminals' plans.