FPS limiter key assignments

I'm finding that the Duke puts quite a lot of stress on my system, and I was getting some hesitation/stutteringin the VC at my KSEA take-off. So, I tried to vary my fps limiter settings which were at 30, to see if that would help.In the documentation, it says that F10 lowers the fps setting and F11 raises it. So first, I removed thekey definitions for these two keys in the FSX Controls panel. Then I found that I could only lower the fps setting,not raise it. Through trial and error, I eventually found that F12 raises the setting and F11 lowers it.So, what I did, was lowering the setting on the take-off roll until the stuttering disappeared.. this happened to beat 22 fps.Pretty neat, and easy to do once you know how. Leaving the FSX setting at unlimited all the time.Just a few keypresses and all is smooth. If I'm flying a less complex plane, or if I'm out in thecountryside, I can raise it back to 30.Has anyone else experimented with these function keys and figured out how to get the fps display on or off?I go by the FSX fps counter and it clearly shows fps going up and down at 1 fps/keypress.Nice to have the flexibility, but a bit confusing since the documentation seems to be out of step with the actual application!