watched a video with john paul jones the other day and he was discussing power octaves. To my understanding this would be like playing a note simultaneously with it's octave either higher or lower. For instance stricking an open A while and the fifth fret on the E string. The purpose is to give more ompf the note. Now my question is just to better understand the purpose and usefullness of this tecnique... or even if my understanding is correct at all.