Hoser1911, for the military, who spends six months at a minimum training their people to fight, and to continue to fight while injured, uncomfortable, or scared, you'll get people who can fight while critically wounded. However, the military spends a lot of effort, time, money, and science indoctrinating and training it's people. That's what basic is about, and that's what PT is about. It's about teaching people that they can continue when their body says it can't. Most civilians don't get that kind of training.
And, again, most civilans aren't going to find themselves in a situation where they are going to need to reload or clear a jam to continue a fight after they are wounded. Combat reloads in civilian life are very rare. So, I stick by my initial statement, for regular people, it's a waste of training time that can be spent learning or practicing something else.
For law enforcement, I can see some value to training to reload or clear a malfunction one handed. Maybe. First off though, don't think the FBI shootout is an example of an everyday event, or even a common police involved shooting. It was so unique, and such a tragedy, that in sent the FBI in on a witchhunt to find something to blame for the outcome. Law enforcement officers may have to reload under fire, because they may go looking for trouble, and may be shooting to not only save their life, but to prevent a criminal from escaping, as happened in the shootout you mentioned. However, and this isn't to put down those FBI agents involved because they did what all FBI Agents would have probably done, but they made numerous mistakes, that probably could have prevented them from essentially falling into a moving ambush, and if they had vests on, rifles or shotguns in hand, and back up closer by, could have let them stack the deck in their favor. If the day they spend learning to reload one handed had been spent learning to wear their vests, or how to follow a vehicle while awaiting backup, they may avoided the whole situation.