Also bear in mind that the frequency the capacitor is operating at is much higher than the frequency that the telemetry will monitor at - the capacitor just fills momentary dips in the power supply. It won't maintain the voltage any higher than what the regular demands of the servo are causing.
Maybe if you have an oscilloscope you might see something more meaningful.
Also, since you don't have any issue with glitching, there is no need to fit a capacitor, and nothing to measure. The caps were only used on Spektrum receivers, fundamentally because they were not well designed.
