"Are we actually doing aikido"?
No, most are not training in the aikido that Ueshiba Morihei lived, but some are determined to bring it back.
Yes, most are training in aikido as exemplified by Ueshiba Kisshomaru, Tohei Koichi, etc. Shown and trained by tens of millions of people, there is nothing wrong with this aikido.
If you think about it, aikido has become the martial art for the masses and the outliers.
Cool answer, Mark, and I particularly like your Hydra analogy.
Still, your answer is so ambiguous that I can't help but post a couple of follow-ups: if O'Sensei fought Bruce Lee, who would win? Can I use aikido to win a fight? Can a katana really cut through a car?
I'm kidding, but (I hope) still making a little bit of a point: practically speaking, what does it mean to study aikido, and what can you do with it?
the answer used to be "THIS is aikido (the way of harmony), and THIS is how you do it." In many ways like a parent or teacher with a young child. Like a child, I had a simple faith that I was doing O'Sensei's aikido. Ten years ago, there seemed to be a broad consensus in books by K. Ueshiba or other shihan, articles on the web, and training at my dojo and at seminars. There were cracks, to be sure (remember the heated debates about cross-training or offering resistance as uke?), but it seemed pretty easy to grasp the essence of aikido.
Now the answer seems to be "I don't know, you figure it out for yourself," which is a much more mature way of looking at things. As you say, one or two of the fingers point back to O'Sensei but there is significant debate on what O'Sensei was actually doing and even whether or not we really want to emulate him.
Most intriguing for me is Peter's discussion of how the current doshu is treating weapons in aikido, and how weapons work was essential to O'Sensei's own training, but not part of his instruction to his students.
I guess the essential question in all of this is whether or not it is possible to get as good as O'Sensei without exactly replicating his own training and experiences.
To put it another way, can a person who pioneered a new skill -- any skill: woodworking, marksmanship, computer programming, whatever -- after going through all the trial and error, distill those skills into core principles that can be taught so that the student is as good as the teacher?
I'm beginning to suspect that the answer is no. The core principles can sometimes be a shortcut, but each student still needs to have his or her own dead ends and false starts to get really good.