One should be a touch careful about basing arguments on 'experienced people' - let me give you a counter example.
Academic research using standard statistical methods have demonstrated the lack of utility of the AWB and the large number of defensive gun usages. These studies have been strong counterevidence to the folk knowledge of some (not all) antigun law enforcement experienced people - like chief of police types who are brought forward to support all gun bans, oppose shall issue laws and the like.
So, you might get what you wish for. Arguing from the one vivid instance and then overestimating the probability of such is a common mistake.
Cho used handguns - experts say handguns kill - ban them.