"Pull development" just means shortening the time in developer before dumping chem and pouring in the stop bath. The MDC shows two different times for Tri-X in D-76 1+1, 9.5 min for 35mm and 10.5 for 120 film. It also shows 9.75 min for iso 400. I would be inclined to develope as if it were shot at 400 speed. You have to remember that the MDC times are starting points, and you must experiment to find the time that works for you.