Red-black trees: An Update

In a previous post, I mentioned a talk by Bob Sedgewick on left-leaning red-black trees, a variant that's easier to analyze, but with the same asymptotic properties. He gave another talk on LLRB trees at the Analysis of Algorithms workshop, and the new slides have (I quote from his email):

somewhat simpler presentation and code than the Dagstuhl version, the discovery that 2-3 trees are also covered, and some fun facts about the analysis that should answer many of the questions that people were asking.

There were many comments on my original post, and possibly these new slides answer some of the questions.