Sure he did - but if you look at what he actually did, there was less actual movement on the knee than there is in most modern suwari-waza. More than that, look back to Daito-ryu and there's even less movement - back before the prevelence of smooth canvas covered mats.
Regardless, the fact that he may have done something doesn't make it healthy for you. He also participated in static stretching - which studies now show to be ineffective at best and harmful at worst, and suffered from various health issues related to diet.
Static stretching is bad? What genius said that? Probably something you're presenting out of context I would say. Plus you cannot take something ie: diet or whatever as a reason not to take what that person said seriously in his field of expertise.
Why are you keeping on with amount 'movement'? The subject is doing suwariwaza. What exactly do you mean abt. 'less movement on the knee compared to 'modern'? It seems to me you are saying something which doesn't mean anything. Perhaps you could explain.