It's not really a question but a bug in mechanical system experience. (2023x cloud)
I create an excitation law to rotate at 10turn/min.
I create also a probe to measure angular speed.
=> there is an offset of 30turn/min (whatever the speed of excitation law ... if 0 turn/mn => 30turn/mn)

In fact it depends on angular sector selected. with the first one => no pb.
the 2 cases are on pictures.
To my mind, the angular speed is correct not the measure ....