Ruger has a video on Signal-Action Self Defense. Maybe it will give you an idea as to what's involved.
https://ruger.com/videos.html?vid=131266939&cat=3782977
Those Ruger videos done at Gunsite are a very good explanation of technique. They cover weapons manipulation and not any of the other important self-defense topics, but at least the ones that are unique to single-actions.
A lot of people carry or keep a gun for self-defense with the simple mindset of "better to have and not need than to need and not have." In other words, they're persuaded that just by having a gun they're better off than not having one. With that thinking, a single-action is a viable choice -- it's a lot better than nothing. Most people who are willing to put a little thought into their preparation for the defense of themselves should recognize that equipment isn't even the most important choice they'll make. But to stay on the topic of single-action revolvers, many equipment chooser's concerns with them, in particular, are the slow rate of fire, the low capacity, and the slow reloads.
There is not much that can be done about the low capacity and slow reloads. Carrying a second gun might be the best solution. But many people are comfortable with just five or six shots. Again, it's better than nothing. I've carried a J-frame with 5 shots and felt it was sufficient. Who can know? With that j-frame, it's a lot easier to miss than it is with a large single action, which also often has another shot. I wouldn't feel unarmed with one at all.
I've found the rate of fire with the single action can match a double-action provided both hands can be used with an optimal technique. Cocking with the support thumb, I can consistently get splits of 0.20s whereas with a DA I might get 0.17 or 0.18s splits. Under stress, I doubt there would be a difference. But there could be a very substantial difference if I could not use the support hand with the single action. I can cock with one hand quite proficiently, but the rate of fire slows way down.
So the question with single actions in self-defense is: are you expecting to be shooting from behind cover at a distant target like when George Patton shot Julio Cardenes at about 60 feet after he fled during an attempted wagon-jacking? Or might you expect to have to shoot an oncoming attacker at 10 feet? We don't trust in the "stopping power" of a single shot from a handgun. That same day Patton shot the horse from under a second adversary at 10 feet, but I believe he was out of his five shots at that point. This is supposed to be the reason he carried two guns thereafter, though he would have hardly been the first to do so. His second gun would address the need for greater volume of sustained fire, but it might not address the slow rate of fire if he were to need to put a charging man down at 10 feet from a compromised position like laying on the ground and if it were to take several shots to accomplish this.
