Every little bit helps. Takeoffs out of Andersen (Guam) on 06R in a B-52G (8 x 13,750 lbf wet) were no biggy, but B-52Ds (8 x 12,100 lbf wet) sometimes popped off the overrun and disappeared over the edge of the cliff (instant 600 ft of altitude), not to be seen again until they struggled back up level a couple of miles out.