It seems to me that we are all in agreement in that there is a very real difference between aikido and aiki-jujutsu and yet we are still arguing. I couldn't agree with you more Nick when you wrote;
"I'm not tyring to be disputive, but as an instructor for 18 years, I have to make distinctions and judgements about things like this. In fact, there are times when I see someone, an instructor or student, and I can say, for my own judgement - His/her Aikido is great - OR - His/her Aiki-taijutsu is great, but his/her actual Aikido isn't.
Ther are many subtle distinctions."
Yes, so you make a judgement on their aikido not on whether or not it is aikido, which is my main concern. Whether we like someone's aikido or not is of no real importance. Judgement of aikido is never objective, it will always be tainted with our own idea of the aikido ideal. Hence I would venture that is why we are all so careful in choosing an instructor to follow. Nobody stays long at a club were the aikido practiced clashes with our personality some where in side of us the aikido we practice must and indeed does touch our very soul over, be the ideal we strive to achieve.
Now for the tricky part. The history of what we now know to be Daito ryu aiki-jujutsu is surrounded in mystery and legend; Minamoto no yoshimitsu grandson of Seiwa, already armed with tegoi passed down by the gods, lived in the Daito palace where he disected criminal bodies. With his new found knowledge of bio-mechanics and the memory of watching a spider killing larger prey still fresh in his mind does he have his epiphany creating Daito ryu .............................................some famous descendants in Kai, a defeat, a move to Aizu. A little oshikiuchi, some Daito ryu,a sprinkle of Itto ryu keep secret for over two centuries and voila.
This is wonderful legend but it must remain a myth until it can be proven and unfortunately it can't.Tthere is still some question as to oshikiuchi's role in Daito ryu jujutsu evolvement. It probably had none. So here is were I am a little vaque but I believe the first records we have of Daito ryu jujustu date from the 17th century when Kunitsugu entered the service of Hoshina. And the first written record of Daito ryu aiki-jujutsu date from 1922 around the time Sokaku visited Ueshiba at the omoto kyo compound. Draw your own conclusions. For more info koryu.com and anything by Stanley(?) Prannin(?).