Hey Carey- you still interested in learning how to
beat the snot out of defend yourself against other people?
If so, skip ahead to about 5 minutes into this video- after all of the cool and scary aikido stuff, where a bald badass British dude is treating a jiu jitsu brown belt like his own personal demonstration dummy:
For me, it's very cool to watch techniques like this from the perspective of a different martial art. You can see what works, and why it makes sense to do some things and maybe not so much to do others. You can see the similarities and differences between various arts. You can see how different both jiu jitsu and aikido are in terms of emphases on specific techniques or ideas.
With jiu jitsu, for instance, you can see that the emphasis is actually on inflicting massive pain through attacking vulnerable points in the body and takedowns, whereas with aikido, the emphasis is placed on joint manipulations and throws. I'm not going to claim that one is more effective than the other- though I do have a few issues with the way people are throwing punches and kicks in the video. They both work. Whether they will work for a particular person really depends on factors that vary from person to person, and I can't comment much on those.
I will say one thing about ground-based fighting. It's damned effective one-on-one in an open environment. Take a stand-up striker to the ground via a joint manipulation or an effective takedown, and he's going to have an absolute devil of a time trying to get back to his feet.
However, if you're facing multiple opponents, or you are in an enclosed space, the time and effort required to take someone down to the ground are factors that will work against you. Taking someone to the ground is usually quick, depending on how you setup the initial maneouvre, but if you mess it up or don't take him out of the fight fast, you could be in a situation where you're just getting up off the ground in tight quarters, and two or more other guys are looking to use your head as a substitute for a billiard ball.
That's not to say that jiu jitsu or aikido don't work in CQB. They do. It's just that, if you're ever unfortunate enough to end up in that kind of situation, you need to be straight about priorities.
First, inflict massive damage- make your opponent(s) regret ever facing off with you.
Second, extract yourself from danger. The longer you stick around, the more likely you are to get hurt.
Third, use any and all available tools. Don't restrict yourself to any one style or technique. Your goal at that point is survival, not looking good or being fancy.
There is nothing fun or easy about getting caught in a fight, whether mano y mano or stereo or surround. (Bad joke, I know.) But if you know a few basic principles about fighting and about inflicting pain, you can at least ensure your own survival. And that is by far the most important thing.