Put on your tin foil hat (Score 1)

FWIW at Dell it worked this way; the phone system would randomly select calls to record or your manager could silently listen in at any time. And yeah, these calls really were used for training purposes (coaching). We didn't have access to people on hold either, now mute is a different story. But this is really simple to detect on most systems... if you hear music you're on hold, if you don't...you're not! Not fail proof but that's what you're hat is for!