I just ordered "Stretching Scientifically" by Thomas Kurz. As of Jan 1st, I'll be keeping a record here of my progress. I'm currently rehabing a pulled hamstring/hip flexor combo, so by then I should be ready to put his methods to practice, and return to the Dojang. I'm expecting great things; as of right now, my side split is ONLY 5 1/2 feet distace from foot-to-foot, and I stand 6'1. That's pretty darn inflexible.
Anyways, I'll post from week to week to track my progress and thoughts!