Thanks both drool@ for his mild frustration with the current
documentation as well as Greg Kroah-Hartman, Heikki Orsila
and Neil Brown for http://lwn.net/Articles/504814/ -- the docs
should really emphasize *why* something is done, not *how*,
as the "how" part is better documented with the code itself
(that doesn't mean that "the big picture" isn't needed).