@wwwillie
Dimming defeats the purpose of using cobs which is to get as much light on the bud sights as possible. Super Cropping is what I have used successfully in the past to tame a monster tall sativa plant. I recommend having some
grafting tape handy if that stock has become woody. Roll the stem between your thumb and forefinger - don't be afraid to put some squeeze into it - until you feel the inside of the stem go soft for about 3 times the diameter of the stem in length; then bend it over to 90° If the outside of the stem tears open
too much wrap it with the grafting tape to promote faster healing. I have tried duct tape and it works but grafting tape seals better and you get a faster heal on the wound. Do this about 6" lower than you first think about because the tip of the plant will turn back up about that much in just a few days. Have some sticks or yoyos ready in case the top is too heavy for the stem to stay at 90°.
That is an amazing plant!