Hey Teo,
I'm not sure what to say except that I had a slightly different experience. I moved the timing on my Castle ICE 80 HV from low to high and back over a series of 10 flights or so and found that high provided no change in RPM recorded by the esc, but did increase the power draw. I could not discern a noticeable change in the amps being drawn, but the net mAhs changed by more than 10% with the high setting having the greater draw of power. I will try to pull out the graphs tomorrow, but my conclusion was that the low timing was best with my Plettenberg motor. I know that is not overly scientific, but at a minimum it offers some added data to chew on
Be sure to let us know what you figure out in the coming days!
Joe