This is a nice thread, OP. Mine grew fastest when I stopped combing so much, and just left it alone. My hair doesn't like to be washed frequently (like more than once a week). I do CW in summer sometimes twice a week, just for moisture, but my hair definitely grows the fastest when I braid it up and leave it alone for weeks at a time. Other than that, bunning and leaving it be also produce great results in the growth and thickness areas.
ETA: You can check out my Fotki for pics from July 2009 vs. Nov. 2009. Those results came from braiding (w/o extensions), using grease on my scalp, washing every 2 weeks or longer between washings, and wearing a LF to let my hair "rest and grow." I don't care if folks think its gross or judge me for not washing for like 3 or 4 weeks at a time while my hair is braided. My hair speaks for itself, and no, it doesn't smell after all that time...I don't overload with products. Sherrylove (if you all remember her) also went several weeks between washings, and has nice, long, past WL hair (the last time I saw her, she did); so did my great-grandma, and so does my grandmother.