I just re-read Kurz's Secrets of Stretching the other day so this is fresh in my mind. Dynamic stretches are to be done b4 the workout, static stretches after. No exceptions.
If you have an extensive warm-up routine like BBoss, you'll have to play around with the order of things.
He likes dynamic stretching 2x a day, 1x a.m. and 1x b4 training.
The book is pretty good, but IMO the DVD/tape is not worth it for most people on T-Nation.