I think it depends on the style of grow you wanna use, it would be good to do it this way if you are going after a single cola. I hear cutting off the bottom branches up to about 6 inches helps the plant concentrate on making the main cola fatter instead of making popcorn buds that won't receive so much light. I saw something about once your plant is taller than 40 inches, the light won't go down far enough for the bottom branches to receive much light anyways. I think the 40 inch depth was for a 400w hid but I could be wrong. If you are going for lst or scroging style, I'd leave everything to maximize yield. Generally, pruning seems to slightly deter growth so you should cut the branches while the plants are in veg. People seem to do this about a week or so before it goes into flowering so the plant has time to recover. Hope that helps,
