Resting Duck??? Why? Can someone explain?

You seem to be asking 2 different questions? Not really sure but I'll give it a try.

Most proteins need to "rest" for a few minutes after cooking. This allow the proteins in the muscles to relax a bit and retain water, i.e. juices. Have you ever cut into a hot steak off the grill and had a bunch of liquid run out onto your plate? Those juices should be in the meat. If you allow your meat to rest for at least 10 mins you will get a much better result.

I assume that they put the duck in boiling water to cook it? I mean, I can't really think of any other reason why they would do that unless I don't understand your question......

So when you roast it the skin becomes crispy.

First prick the skin, boil it, allow to dry, then loosen the skin from the meat.

Many also blow the duck. If you tough enough, you put your bare
lips to the ducks neck and blow the skin away from the meat, then
quickly blanch, and hang to dry for a day. You can also use a small
shop vac and place the hose on the hole that emits air, its a lot nicer
than doing it bare lipped. It will make your duck skin much crispier and
help with rendering fat. Good luck!

Blah, just use a straw.

Blowing ducks

Just like in eat, drink, man, woman...