In rec.aviation.student Andy Hawkins wrote:
The PAN actually sounds to me like a good idea, but as I always say I'm
still a lowly stude! Being able to differentiate between a Mayday (basically
aircraft in imminent danger) and PAN (something that needs priority but
nothing that will endanger the aircraft in short order) seems like a good
idea to me.

Given the rarity of emergency calls, it seems like the important thing is
to make the emergency known in a simple and easy fashion first, then work
out the details later on as they're needed. The distinction is useful, but
I think that it's not worth putting extra workload on the pilot to figure
out just what degree his emergency is in his moment of crisis.

--
Michael Ash
Rogue Amoeba Software