Peter A Goldsbury
I think this is partly a matter concerning the fluidity of definition. A more precise question would be: which postwar manifestation of Daito-ryu is closest to what Morihei Ueshiba was actually doing during the years he spent in Ayabe from 1920 onwards? (Remember that there are also Admiral Takeshita's notes, which I think begin from around this this period.) Then, there was the move to Tokyo in 1927 and the beginning of another period, between 1927 and 1942, which would involve Hisa Takuma more directly.
Hmmm ... well, would Iwama style be just as much in line as the Takumakai? I don't know much about Saito or what he learned, but there's the often cited passage about Saito and the Budo manual. How close are Iwama style aikido and the Takumakai syllabus?