. . . this statement, while perfectly reasonable on the surface, implies that the author enjoys a shared perspective originating in the knowledge and experience indicated in the text.
Again, this statement implies a perspective based in proprietary knowledge and experience that allows a) these specific individuals to "incorporate much of the training O-Sensei did" and, b) the statement maker to determine that they do.
I think I have not been clear enough about my view on this. I include myself in the group that does not have much in the way of the "proprietary" knowledge and experience discussed. Like you I trained with a direct student of the Founder but my own teacher, while talking extensively about his experience training with O-Sensei did not have us duplicate his actual training regimen. So there's no question that I started with nothing more than a sort if "Saotome Ha"
Ueshiba experience. And while having its own validity, it could be completely different than your own "Shirata Ha"
Ueshiba experience which stand on its own.
While my ideas about these things are a work in progress, thanks to the efforts of folks like Peter, in the end I will probably only be able to speak with any authority about "George Ha Saotome Ryu Ueshiba Aikido"
and my personal experience on the mat informs these ideas more than anything else.
As for others, it is only with the objective academic work done by people like Peter G who provide us with constantly evolving perspective on what the Founder did and did not do and say. So there may be folks who are structuring their training to match what they believe the Founder himself did, but that assessment changes as more research is done. So while they do have a sort of proprietary experience that the rest of us may not have, it doesn't mean that their picture of the Founder is true in any final sense either. But I value the input these folks have as it is very different than my own experience.