I'm curious how you would reconcile this, from Gaku Homma, undeniably one of the last of the uchi-deshi ...
In the last few years of his life, the Founder sometimes fell prey to spontaneous bursts of anger, and everyone was fearful of his outbursts. Eventually high ranking shihan or shidoin quit coming to visit the Founder at Iwama all together. Fearful of his wrath, if a shihan did venture to Iwama to visit they would ask the late Morihiro Saito Shihan, who lived on the premises, about the Founder's mood and state of being before asking for an audience. If he was not in good sorts, they would leave quietly without seeing him, stopping only for a moment at the dojo altar to leave a gift of sake and a donation on their way out.
In those last years, even at Hombu Dojo in Tokyo, when I would arrive with the Founder as his otomo (attendant), the staff would ask me first how the Founder was feeling that day. If I told them the Founder was not in a good mood, shihan and administrators alike would disappear. Everyone was afraid of the Founder's bad temper when he was in these moods. It was a sad experience I had many times in the last years with the Founder.
For me this is quite simple really due to the way I look at things from my perspective. As I have said, and got in trouble for, that I understand Ueshiba and I understand Aikido. Thus I hold understanding as the key.
Simply put, he was going through something. There was something troubling him, something he was a bit frustrated with. To say I understand what it was would be merely conjecture and maybe a nice exercise for the creative mind but thats all it would be. He could have been frustrated with the way things were going or with the fact that others still were not quite getting it or even with some personal aspect, but as I said that's all conjecture and thus of no worth.
The one thing which is certain is it was a barrier of the heart he was addressing. The love side of Aikido. Maybe frustration with others not coming to terms with that aspect and thus finding he had even more to discover there himself for it was expressing itself as anger and frustration and mood.
This I see clearly personally and not therefore as a fault but as a sign of someone on the path going through a barrier of some kind. Being a very expressive person in demeanor and spirit and presence this would thus affect those around him in a more pronounced way. That's all really.