Has there ever been any evidence to support that? We hear of criminals getting guns and killing people, but have there ever been any cases of somebody who has a legal permit to carry killing anybody by accident or just going on some random shooting spree? There are hundreds and hundreds of cases where the person who killed the attacker was a had a permit to carry and used their weapon proficiently.
There are guys in my area who teach the concealed class who go on and on about how bad it will be if just anybody who has a gun would attempt to defend themselves without the proper training that only they can provide. I'm not against more training, but from what I've seen, it's more of a tool to get people to pay them money.
I think that law enforcement has the most training and experience when it comes to dealing with a shooting situation. Here in Tyler, there was a shooting at the courthouse that went on for quite awhile, then the shooter left the courthouse and drove to another location before finally being killed. Several officers and civilians where killed. Thousands of rounds where shot without hitting the shooter. All the training and experience disappeared when it came to actually aiming at the guy they where all shooting at, and who was shooting at them.
https://en.wikipedia.org/wiki/Tyler_courthouse_shooting
In Paris the police got there too faster then normal due to a training exercise that was going on in the area that included multiple ambulances. If that had not have been the case, the number of causalities would have been much higher.
I don't know what will happen if I am ever shot at, or if I feel the need to shoot at somebody. I don't think training is the answer, it's how some people react to a situation. Some will fight, some will run, most will freeze. All I do know is that I do not want to have to hide or run with the hope that the police will show up and be able to stop the shooter before I die.