I repeated yesterday's flight, without the distraction of the camera, and still came to the same conclusion.
There's nothing obvious in the flight behavior of my CAP to match the ballooning characteritic.
I did move the c.g forward to 32% to desensitize the elevator, and changed to a 10 oz tank from a 6 oz.
In flight trim is 1 degree nose-up on the elevator, close to what it was yesterday.
Now it snaps out of the top of a loop, instead of the bottom. An improvement!
Next flight will be with reduced low-rate on the elevator.
Overall, the behavior of the plane is quite normal in all speed ranges.