Re: Aikido on the ground, questions.
I have been thrown in a real fight (rolled back onto my feet), but in another fight I have been tackled (trying to run-away from multiple attack - I do not recommend running away for this reason!) and ended up on the ground resulting in a very scappy situation.
I don't think aikido gives you any ground-fighting capabilities. Although 'wrist-locks' can be applied, usually the action is too fast from a prone position. Indeed I think a large amount of 'ground-work' in traditional martial arts is rubbish. Fitness , aggression and determination is a prime requist for survival in this position.
I would say aikido does help to prevent you from going onto the ground, but I assume traditionally the idea was that if you were on the ground you were as good as dead. Eye gouging is probably one of the better techniques from this position (but, obviously illegal in sport wrestling/NHB).