I don't usually bury the potset - I find the blue foam cozy keeps it mostly unfrozen in all but the worst cold, and even then it ends up just a crust on top. If I need a drink at night I get into that, but usually I don't.

Now peeing on the other hand - that's what an empty wide mouth pepsi bottle is for - fortunatly that usually only needs to get used once a night, so I tuck it into a roll of clothing when done and it usually stays unfrozen enough to empty it in the morning. Having to decide what to do with a frozen pee bottle when packing up sucks! (and no, I'm not getting out of the bag at -20 to pee.. that's uncivilized!)