his hands are placed in a particular position, contrary to the formal balanced positioning of the hands you see in almost every other picture of Osensei. He was teaching something important. (Note attached photo at bottom of this post)
After carefully looking at the picture I also noticed his one ear is redder than other one. That's direct hint for important spiral teaching. The last one, his left eye is looking down while right one toward the ceiling -- clearly heaven/earth teaching.
Also there is a famous story of a student from Europe. He was uke for O sensei and noticed that O sensei farted every time he was doing irimi. He didn't speak Japanese but he learned important teaching well. He thought "Yes, this is clearly a hint O sensei gave me. I got it right in front of my nose! "So after his return home, he and all his students also farted when doing irimi. After reading recent discussion, I personally believe he missed ‘6 directions' part of farting.