This is more like a curiosity than a technical question.

I was curious to see how fast my computer could go when running a heavy Flash animation. Then, just for fun, I put a few animated characters walking on the screen, and started playing with frame rate. I began with 30fps and went increasing it, and for my surprise, when I reached 240fps I noticed that it seemed to be stucked in the same speed. Another interesting fact is that by increasing the number of concurrent animated characters on screen clearly made the overall speed to decelerate.

What is very strange for me, is that my CPU usage barely touched 40%, and therefore I still had a LOT of free CPU to support Flash! But instead to use more CPU, it simply lost performance.

Maybe there is a Flash inability on manage efficiently computer resources when there is too much animations to control, even if the CPU could easily afford it???

Anyway, it seems very weird to me and sounds like a not properly optimized Flash core code.
In my 25+ years of coding, I never have seen a compiler or interpreter to limit itself.
Normally the processing speed is always limited by processor power, and the language core will always try to run at full-throttle CPU.

Any thoughts?

PS: Flash CS4, AS3
CPU: AMD Phenom 2.4 GHz quad core