SetPulseWidthPosition()
doesn’t seem to do anything. 
We are using CAN Talon’s with the CTRE Magnetic Encoder. We are trying to establish the zero position of the encoder so that it is consistent between two encoder of these encoders.
We are trying
_talon->SetPulseWidthPosition(_talon->GetPulseWidthPosition() - kZeroOffset);
The idea is to give a consistent zero location for the absolute position.
We could be approaching this wrong as the manual suggests using the absolute position to establish a zero for the relative position. We haven’t been able to work out that series of calls.
Even just calling
_talon->SetPulseWidthPosition(0);
Had no affect.