What's the norm for packing technique on a belay parka or other insulating layers?

Do you just leave room at the top of the back to accomodate the "jamming it in there so i can't quickly get it out" method? Do people normally take the time to get them in and out of compression sacks?

Does anyone just strap a layer to the outside of the pack if you know you'll be adding/shedding that layer frequently? I don't see any harm in doing this as long as conditions aren't conducive of watching a couple hundred dollars of feathers and nylon dissapear or get soaked. Does anyone have experience or lesson learned on this?

It depends what else I'm carrying, how big a backpack, and what kind of route.

Most frequently in winter I'm doing mostly hiking, at least partly below treeline, with a big pack that's decked with snowshoes, microspikes, and often an axe, sometimes two.

Belay parkas need to come on and off quickly. Inside the backpack, on the top, is my normal winter method. I keep the stuff sack in an internal pocket of the parka, and I use it at least some of the time - it keeps the pack tidy so you can find other stuff with less risk of pulling out the parka to search and watching the parka blow away, and it can actually save time when retrieving the parka, since it comes out of the pack more smoothly.

Back of the pack (or under the lid but outside the body) is a frequent method for hardshells if I'm not bushwhacking, but in winter I often have spiky stuff on the back of my pack that I want to be able to reach without worrying about slicing open an expensive parka.

There's no normal, it's about what's going to work for you. Sometimes I have a down jacket stuffed into a stuff sack somewhere in my pack... other times it's a synthetic at the top... other times it's stuffed into the lid... other times it's just stuffed under a compression strap on the outside of my pack. Just depends on how cold it is, how hard we're climbing, what we're climbing, how long the pitches are, etc.

Most of the time, I just freeze my ass off while my jacket stays in my pack.

If I am climbing something where the jacket will come on and off regularly, it is just stuffed into the top of my back.

I don't use a stuff sack and I wouldn't strap an expensive down jacket on the back of my pack. It would get trashed. For ice-climbing, I use my big belay jacket to hold everything in place inside my pack. So I have the rope against my back, gloves, harness etc sort of holding it there, sharp metal gear in a stuff sack or strapped to the outside of my pack (crampons, axes) and then I shove the down jacket into the space between the rope and the back of the pack, to keep the rope close to my back. This is for approaches, of course. On approaches, I'm typically not getting my belay jacket in and out of my pack because we rarely stop. Once we start climbing, all the gear is out of my pack and I have a mostly empty pack to stuff my jacket into when it's my turn to climb.

For winter day-hiking/snow-shoeing, I just do pretty much the same thing and shove my (smaller) down jacket into my daypack where it's easy to grab. But I don't really stop and sit around in the winter so it rarely comes out.

Under top strap, or in mesh back panel depending on weather.

I almost always put my belay parka on the back of my harness in the stuff sack. That way I can reach back and yank it out at each belay, before I start to cool down.

While in the army I have learned techniques for packing.

For the outer jackets with hood. Close the front velcros or drucker buttons at the front, but don't zip up the jacket. Lay it flat in front of you with front side up. Now fold one side like you would normally fold a long sleeved shirt, but make it as wide as opening of your hood. Repeat on the other side.
Now just tightly roll your jacket from bottom up.When you reach the hood, jam the roll inside of the jacket hood to keep it in place.
I hope this explains, even though there are no photos.

P.S. found online guide
http://frontierbushcraft.com/2012/03/13 ... eat-trick/

As for down jackets. Just jam it inside one of its pockets, like you would with a sleeping bag in a compression sack.