I was checking out in a Civil Air Patrol 182T the other day and the
check airman pulled the power on me. No big deal, but then he
demonstrated how the glide improved when the propeller was pulled to
low RPM. No one had ever showed that to me before.

Question is:

In retrospect it seems obvious that there will be less resistance when
the prop is closer to a feathered position. Buy why don't I see this
as part of emergency checklists for airplanes with constant speed
props? What am I missing here?