Is there any hope for a person to figure it out themselves?... if they cannot get access to a teacher of this high caliber?
Learning by yourself. Lets talk about that.
1. Initial discovery by yourself?
I think its damn near impossible. Maybe a few things I dunno
2. Adding on to what was shown?
Yes. Most certainly
3. Making "advancements" all on your own?
I think that depends on what you were shown, how smart you are, where you do further research and how and how well and how often you train.
There is no doubt that the greats kept picking up stuff as they went along. They openly talked about it. But I think we need to leave those comments and the validity of them- to the established greats who can get away with it.
I am only speak for me Josh. There is no "establishment" out there that is in agreement of what is correct. There is agreement and disagreement on things. And I don't consider my self in terms of high or low calibur, nor do I consider myself a teacher. I do what I do and go take it out for a spin when I am able. I tell everyone to to leave and go do their own research. if they come back fine, if they find something great...show.
Go feel the best you can find and validate your own stuff.
Are there any principles that you can outline in helping to build the budo body? Is self study to *build*, a realistic possibility?
Not on the net no. I think its waste of time to do how to's. Even up close and personal it takes a lot of correcting over many practices. Personally I just feel its a better walk than doing more kata. I left traditional Budo with some very good details and principles, studied diligently and came back to find my efforts were not without merit.
I can't address all of that stuff you are talking about. For me spiral energy is there all the time its not about offensive energy. You can absorb along a path or emit along a path or carry along a path or send. There is power at every arc and it is supported by the opposite. Its why I never liked reading where people stress the idea of the single push/ ground path thing that Tohei showed as Ki or Kokyu. Power and aiki is much more than that stuff. And there's a good example of the disagreements with this stuff. Some say that stuff is the basis of power, others will say spiral energy is the basis of power.
I'd save your money and go find *someone* willing to show you some things. Then... go search out others who *strongly* disagree with whatever that *someone* says. In time you'll know where and what you want to train. I just couldn't spend the rest of my life grabbing wrists and taking Ukemi when there is so much more to be had.
Enjoy the ride.