And you are creating a contradiction where there is none.
Yes, of course O Sensei did different things to fit the situation. But all of those things were driven by the same fundamental principles.
I never had the opportunity to train with O Sensei, but I'll bet the people who did would say that his off-side arm, "dangling" or not, was about as "dead" as a lightning bolt.
The principle of Aiki which means absolute non-resistance, manifested in timing, body positioning, leading, blending, Etc.