Re: Aikido does not work at all in a fight.
Mathew are you talking about Jason Delucia? I value his opinion, but would not say he is "god like" around here. I don't believe anyone is for that matter.
Nikkyo, sankyo, yonkyo, gokyo are certainly valid submission techniques, that is not in debate. The problem I have had is getting to them in a fully resistive situation. I have landed nikkyo once in the last year, I use sankyo as a temporary controlling technique regularly. Yonkyo has proven to be useless and can't remember ever using gokyo. Ikkyo I have used the principles of everyday, not as applied in aikido though...in principle.
In a fully resistive environment, they always have options unless you control their balance or center (dominate). Even then it is difficult to submit someone with these techniques....at least in my experiences.
Does not invalidate them as a training methodology, and they do come more in to play with weapons. Weapons can change the dynamics some....however even with weapons, the best plans and technique end up in something other than what you practice in a controlled environment. (Matt makes this point clear).
When you are training from effectiveness, you train for a "70%" solution and isolate failure points to mitigate them. When you train for principle and perfection as in the DO arts, you do not concern yourself with these "points of possible failure", and train the whole spectrum of principle.
I think you have to be careful not to confuse effectiveness, with principle. Where Matt and I would differ is I don't think it is a necessarily a waste of time to train principle. However, I agree if you want to be effective, you don't necessarily need to waste your time studying principle oriented practices.