HAH, what are the odds? You see that sudden dip in the power spike in your graph? Inboard engine cutoff. They had to shut down an F1 engine to prevent the combined thrust from tearing the ship apart.
I saw the Apollo launches live on TV, by the way, when there was such a thing. Watching all those vapor plumes in the upper atmosphere had me on the edge of my seat.
https://www.youtube.com/watch?v=-rM1RA2Jmh8
When the first stage separated, it was only 60 miles downrange and 40 miles high, but that was most of the work.