It's probably a misapprehension of the advice to burn long hot fires,
to warm the chimney enough to keep creasote from condensing there.

I dunno why you'd wanna do that, though, when you can scrape it
off with a wire brush and use it to treat your fence posts when
nobody's looking.

OK, here is another question. My chimney goes up about 6-7', and then bends.
Last year I had it inspected, and they inspected up to the bend only and
said that buildups only happen in the first 6 feet or so. Is this true? How
far up the chimney do I need to clean, how far up is creosote likely to
build up? I have a steel double layer 6" (I think it's 6") chimney.