Pretty old thread, found it on Google. But Likely the acronym COG paired with LST, means a sort of circle LST method where you continue to LST your plant into a circle around your container. This gives multiple tops, but I would def make sure you have hella root space. This method would work perfectly if you are interested in a SCROG grow. (Screen of Green). If I am wrong in any of my information, please let me know.