Despegue,
"It is PURELY the decision of the crew whether or not to declare a pan pan or Mayday. You are NEVER wrong in declaring an emergency if you deem that the aircraft is in imminent danger."
You are absolutely right, Sir. As an ex D&Der I would much rather have the pilot declare the highest option and subsequently downgrade it as appropriate. It enables us to get all the beans in a row in a timely manner - we can always stand units down as required. That is much better than having to play 'catch-up' in a fast deteriorating situation!