Now that's an interesting idea!
Are these mokuroku confirming the teachers ability to consistently perform those techniques with aiki? Could that be why they are all different? Different students/teachers taught different things that result in different expressions/waza?
Are you discussing the Mokuroku they were given by Takeda or the syllabus they taught?
Where does the ten Gen of Sagawa and Sagawa's method of imparting Aiki, match up with the hidden mokuroku, goshin yo-no-te etc. that he was given? And how does that compare with the Hidden Mokuroku of Tokimune (which he states he re-organized) and their public and private opinion of the aiki of the Kodokai and Roppokai, and all of that compared to the syllabus of the Kodokai and then compared to the Soden of the Takumakai? Now add in Ueshiba!!
And where do they all teach in a consistent, organized, step-by-step process that matches the scrolls, school to school, as in the koryu that follow their menjo?
Now there's an interesting discussion. Where did Takeda make it up as he went along -and his students (who got it) simply followed their teacher's example?
I suspect that the ones who were bright enough to pursue it (after Takeda gave them the methods for internal power/ aiki) and develop it- walked into another of the shining attributes of this work. Awareness, inventiveness, a universal potential in all things, and continued growth. Internal power / aiki is formless and it continues to both create and reveal. The same talent and ability that first imparted it to you doesn't simply go away...it grows.
You simply keep changing.