This is the call:
myRecording = ScheduleHelper.ScheduleRecording(NPVREvent, true, pre, post, DayMask.ANY, 0, RecordingQuality.QUALITY_DEFAULT, false);

Code stolen from NEWA follows this up with:

if (myRecording.OID != 0)
myRecording = ScheduledRecording.LoadByOID(myRecording.OID);

I assume that it is verifying that it added the recurring recording successfully. In my limited number of tests, however, myRecording.OID is always zero, even though the call was successful.
How should I be verifying the success or failure of the ScheduleRecording call?