This has been bugging me since I read it before the weekend, so since I thought I'd cycle back and pick up on it.
I think you're overstating your case, Mark. Yes, O-Sensei trained Daito-Ryu, taught Daito-Ryu, and handed out rank in Daito-Ryu before the war. But I think the history is clear that he did more than add a spiritual ideology to DR. He personally came to a split with his teacher that seems to have been more than just personal; he came to a point where he started to look for another name than "Daito-Ryu" to describe what he did; and those who saw what he did saw something other than Daito-Ryu in it. He may not have come up with the name "Aikido" himself, but he seems to have been clear that a new name was needed--he was calling what he did "Takemusu Aiki" before others suggested "Aikido" to him. And he clearly made choices in what he presented and how he presented it, as much in what he left out as in how he refined what he kept.
Don't take it personal, but I'm going to ask you to support some things.
First, you said, "He personally came to a split with his teacher that seems to have been more than just personal". So, is there anything out there that supports that? His split was more than just personal, I mean.
John Driscoll does an excellent job of correlating Daito ryu and aikido techniques here on Aikiweb. The end result is a very high percentage. Mochizuki laments the fact that Ueshiba pared down the Daito ryu syllabus ... not that he changed it. Then we have interviews that state Kisshomaru and Tohei changed the syllabus. So, we have to look at what Morihei Ueshiba was actually doing and *not* what Modern Aikido is doing.
An older Ueshiba on video still does stock Daito ryu techniques. He still uses atemi to incapacitate an attacker (just watch some of his videos where he uses an atemi motion to simulate a strike to a downed uke's elbow). Kodo and Sagawa did very similar demonstrations as Ueshiba. Kodo is on tape doing the push test from a seated position. Ueshiba carried a fan just like Takeda. Where in Modern Aikido does this happen? Then there's the issue with the money.
IMO, what Ueshiba changed in Daito ryu techniques was that he opted for another choice. One in which he opted to spiral the attacker outward into safety rather than the Daito ryu conviction of maim/kill. And even that change is suspect because an older Takeda is quoted as stating that his vision of Daito ryu was self defense. Was Ueshiba just taking a natural progression that Takeda had already found? Or did Takeda take a different path because he had seen what Ueshiba had done?
You said, "he came to a point where he started to look for another name than "Daito-Ryu" to describe what he did". Yes. When? After his split with Takeda. Until then, even up to the opening of the Kobukan dojo, he was still a Daito ryu man. As Sagawa stated, there is a time when the student branches out to do different things than the teacher. Ueshiba followed that progression from a spiritual perspective. Sagawa kept the name, Daito ryu. Yet, both said what they were doing was different than what Takeda had done. But both were Daito ryu aiki men. So was Kodo. So, what other reason was there to look for a different name and what research out there supports that?
You said, "And he clearly made choices in what he presented and how he presented it, as much in what he left out as in how he refined what he kept". Yes, Ueshiba did. However, aiki was the foundation for his spirituality. Take a look at Seiseki Abe as an example. Around 1952, Seiseki Abe says this about his initial meeting with Ueshiba:
"How did you ever learn such a wonderful budo", and he answered, "Through misogi." Now I had been doing misogi since 1941 and when I heard that Aikido came from misogi, suddenly "snap", the two came together.
Seiseki Abe had been doing misogi for at least 10 years before ever starting aikido and wasn't at all near Ueshiba's skills or abilities, nor did he even see misogi and aikido as being similar. However, under Ueshiba's tutelage, Seiseki Abe continued to grow as a martial artist. We can see from this that something that Ueshiba knew and had trained was the underlying basis for powering his misogi exercises. Other people who did not have that certain something did not grow to replicate Ueshiba's abilities. Are there other Oomoto kyo, other misogi-type people, other zen adepts that have done what Ueshiba, Sagawa, or Kodo have done? Where are they? Why did those three consider themselves peers even though they were doing different techniques?
Daito ryu aiki men through and through. Ueshiba just took the road less traveled compared to his peers.