I am sure the instructor is more competent than me and doing a better ikkyo. But it did not look so completely different to what i was trying to do. If after trying to apply ikkyo for nearly 5 years in every conceivable variation it is just my own incompetence leading to failure then I have to wonder whether aikido is just so subtle and complex as to be impractical for self defence purposes.
But of course in real life no technique is guaranteed to work as if often said or we would only need one technique.
But how far is an uke supposed to resist a technique? this just standing as stable as possible and resisting every movement seems to be a strange way to practice aikido to me and certainly is very frustrating. He is not really attacking me and knows in advance the technique I will apply so can just muscle in the opposite direction. This training partner does the same thing when acting as uke with other people-so it is not just me.
Although it is only one person it is only a v. small dojo (so not always a big choice of partners)- and I have the impression that other people are starting to copy this resistant uke model.
I think bringing self defense into this conversation is something of a red herring. A real attacker wouldn't just be standing there waiting for you to do something. There are plenty of challenges in applying aikido in a self-defense situation, but that's not one of them.
As for what your instructor is doing differently, maybe you should ask him? And likewise the question of appropriate ukemi. That will vary depending on what exactly is being practiced.