I have read many people talk about pinning their hinges. Is this just a matter of drilling a hole and putting a toothpick on each side leading and trailing and then epoxying them or ca'ing them?

Yes that's the way I do them (We have mostly ARF's in our Hanger)

I measure the thickness of the element to be pinned and carefuly drill the holes from the underside making sure that I have drilled through the actual hinge (I use an old style of hand drill for this - one of the ones that uses a geared crank to turn the drill) but make sure that I do not drill all the way through the top covering - This way the plane still looks OK without the ugly pin showing.

I use Epoxy (instead of CA) to hold the pins so that the excess epoxy seals the opening where the pin is inserted.

That sounds good to me. I havent ever had to do this yet but I might start. I just bought a Cap 580 and will probably to that.

I do it the same way. I cut my toothpicks a little short so they won't protrude from either side. I use ca on mine, it really wicks in the hinge thru the toothpick. I then use a hole punch to punch out some covering and cover the holes up.

It will keep the hinge in place if the glue fails not if the hinge tears
you can also use a piece of push rod guide tube chuck your drill bit in a pin vise cut the tube to leave only the depth you want to drill exposed put a piece of blue painters tape over the hinge area mark and drill to the stop glue the pin in and if you want take a paper hole punch and make a covering material patch patch to hide it