reddit/reddit — pull request #926 by dls (2013-12-10 04:40:10+00:00)
Title: Adds comment to _hot to avoid confusing people

(for an example of the level of confusion the uncommented version can cause, see http://technotes.iangreenleaf.com/posts/2013-12-09-reddits-empire-is-built-on-a-flawed-algorithm.html)