trimming the right leaves at the right time in its developement can be vary good, if u trimming the lower leaves u can actual get a better vield from ur plants, even taking off the bottem branches(4) WILL MAKE U HARVEST MORE ON THE OTHER BRANCHES, if u hav all the braches all the food and energy is split up so every thing is growing at same rate, but if u take of the bottem braches ur giving the other branches more energy and food making them veild more