In the "Floating Bridge" article,I find support for my interpretation of "masakatsu agatsu" not as "victory over oneself" but as "victory of being oneself," more or less.
From the Floating Bridge article:
"Ame-no-minakanushi was the first deity to appear in heaven - in other words, the "Boss" who stands in the center. ...Ueshiba says that you yourself are the "Boss" - as in 我即宇宙・宇宙即我 " I am the Universe, the Universe is me.". This is a very simple, but very important and powerful point."
To me, masakatsu agatsu means winning the right or freedom to be oneself. It's the right we wanted to gain when we sought out martial arts.
And this part made me think of Itsusu no Kata in judo, as demonstrated by Kyuzo Minfune:
"The "Boss" stands on the Floating Bridge uniting the opposing In-Yo forces and moves in a spiral..."
The third exchange is what I mean, but it also appears in the fifth.
Very interesting points.