Re: Shomenuchi nikkyo
If you look at early Ueshiba video you can see a sequence in suwari waza derived from aiki-jitsu, all from shomen-uchi: irimi-ikkyo, tenkan ikkyo, nikyo etc.
I agree that shomen-uchi nikyo is practically not useful, but often what we are learning is to move from one technique or body position to another. Thus it is useful to learn how to do nikkyo from a position in which your hand is already grabbing the wrist (ikkyo style). Also, talking about utility can be a bit self-delusional, suggesting that what we do in the dojo is realistic rather than just training.
Don't know why this thread has taken a harsh turn. I think its useful to recognise that we're all on a journey in aikido so I wouldn't be as harsh as to say that the sensei is wrong - I'm not sure that he has got somewhere where I don't yet understand or vice versa.