I see your *snort* and raise you one *hmph*. Yeah, sure that's possible too. But also conjecture. I could retort that the pre-war guys who left Ueshiba to found their own schools, of whom Shioda was one, reputedly did so because they weren't "getting the goods" to the degree they knew Ueshiba had. I doubt very much that Shioda had the "peng" with which to drive aiki-sage (which he really seemed to like. A lot.) and aiki-age. If he'd had it, so would Tohei and the rest, and it would have informed their styles of aikido when they founded their schools.
Without the aiki, Shioda would not have had the knowledge nor the body wisdom to manipulate his scapulas with his famous "Attack my chest" aiki-sage move. Nor would he have had the sophistication of movement in his meimon and tandan in aiki-age. Those actions are parts of a very specific Daito-ryu-with-aiki training and would not have been gained casually through occasional "exchange" with those "ancestor/cousins" visiting his dojo. He had to have been trained by someone. I doubt very seriously that it was Ueshiba. The circumstantial evidence of Kodokai "trademark" techniques points the finger naturally toward Horikawa or one of his senior students, over a period of time and not casually.
Cady, I call your *hmph* with a *bah* - you can't dismiss my counter-conjecture to your conjecture by calling it . .. conjecture. You'd then have to support your statement that pre-war students left Ueshiba to found their own school cuz they weren't getting the goods from Ueshiba . . with more than conjecture.
The fact is there are at least three discrete examples of pre-war students that left Ueshiba to found their own schools who were each able to manifest peng jin (and apply it as aiki) within their respective offshoots (Inoue, Tomiki and Shioda). Which sort of runs counter to your doubt that Ueshiba didn't pass along some very specific Daito aiki training. And if your biggest argument was that Shioda had to have the body technology to make the Kodokai "techniques" work, I could see as likely an instance where he watched, thought they moved a bit stiffly and thought "Hey, I know the body secrets here, I can do this better than THOSE guys!".
Ain't this speculative stuff fun?!