I'm not going to slog through this entire thread -- I've got things to do today -- but I hope someone has noted that most of these shootings occur in places that have been designated "no guns allowed"?
Schools are generally "no guns" and the theater in Aurora posted "no guns" signs. The shooter had plenty of options to choose from for his murderous spree -- but he chose the Aurora 16 theater because he knew no one would be armed. It was not the closest theater to his home, or the largest one. It was the unarmed one.
Deranged individuals do what they do because they are deranged, not necessarily stupid.
That doesn't mean some deranged individual may not be stupid enough to go try to shoot up a police station full of armed officers.
By the planning some have done beforehand, I would say that yes, those were not too stupid.
Maybe the stupid ones are the ones that get caught before they follow thru with their plans?