i let the bottom branches go until like 2-3 weeks into the stretch phase of flower, that way they stretch out some and make extremely good clones, i also lst for lots of multiple top colas and sort of lollipop the bottom 4-6 branches on each cola and make them into clones. Last time i got 60 useable clones off of my main plant w/o touching any of the good branches. cloning and re-vegging create really bushy plants btw, so that helps too, but anyway, i kinda got off topic, but thats how i do it.