My L3940 HST has an Auto Throttle Advance lever. Move it to "On" and the HST pedal responds by increasing or decreasing the speed and engine RPM, much like pressing an accelerator. Move it to "Off" and the HST pedal keeps a constant speed and the engine RPM must be increased by the throttle lever. I'm just curious if you have this on your tractor, do you keep it in the "On" or "Off" position and in what situations would you use it? Thanks for your time.