In the article, it was pointed out that, for a variety of reasons, most of the post-war uchi-deshi had limited direct instruction from O-sensei. Isn't this true of Saito as well? Although Saito trained with O-sensei at Iwama directly during the war years, I seem to recall reading somewhere that his attendance was limited to once a week or less, due to his job as a railway porter. Is this true?
Also, it is a fact that O-sensei promoted Tohei 10th dan during his lifetime, not Saito. Doesn't this argue that the founder of Aikido felt that Tohei had the better understanding of the art? Is that relevant in terms of technical mastery or the techniques?
Saito had an odd schedule, so he'd work intensely followed by a number of days off during which he spent all of his time attending Ueshiba. He and his family cared for Ueshiba all through the 50's and 60's. In terms of actual contact hours it's hard to argue against him - that doesn't mean that he was better than anybody else, just that he was there.
Ueshiba promoted a number of people to 10th Dan before Tohei, were they better or worse? He gave a Menkyo-Kaiden to Roy Suenaka - does that mean he "got it"? Without disparaging Tohei (for whom even Saito had great respect), I don't think that Ueshiba really cared that much about the ranking system - things like that just didn't interest him very much.