Interesting thread. The Champ was reluctant recently in severe cold until it was suggesting priming each cylinder in turn. This, plus
leaving the primer out while starting & pushing in when the engine fires
which had also been suggested in the same manner as Cap'n Smithy's post, did the trick and today she started beautifully.
And as today was the first time I've ever flown off a decent covering of snow, it was especially rewarding.