I have a mother vegging. She was really tall and stringy when she was given to me. I just experimented. I turned her from a tall scraggly plant into a very short bush by Lst'ing her, topping, super cropping and singing out of tune
. It's fun to have a plant that you don't really care about to experiment with. At one point I even cut off the top 6 inches. Mj is pretty hearty.
This is all good info though. I never really knew when to top. Now I know.. Here she is on the left in need of a drink with my hps turned off.