I needed to figure out how to purge the air from a keg, and after a bit of looking found a great description in this answer to the question "Do I need to completely fill my keg?"
So now I know how to purge a keg. Great! But wouldn't it have been nicer if the answer had been for a question like the one I had, rather than for this other question?
I'd ask my question and answer it myself, but I don't want to just steal @Brandon's wonderful answer, I want to somehow just port it over or make a pointer to it. And besides, "How do I purge a keg?" is already similar to "Do I completely fill my keg?" - similar enough that I was able to find it, anyway.
So what's the right thing to do?