While I'm not a big fan of typical defoliation, I have heard soooo much praise from reputable growers that I am experimenting. I don't remove leaves unless I can justify it. I have heard, DO NOT take more than 20% off any HEALTHY plant at any given time. My technique is limited to; leaves that block light from flowers, leaves that are damaged beyond 80%, and, that's right you guys...I did it...leaves not supporting buds. Your plant is a little solar factory, everything happens as a result of photosynthesis; 6co2+6h2o in the prescence of useable light= c6h12 o6+6 o2, when the o2 rises to a certain elevation in the atmosphere it bonds with another free o molecule and becomes o3...which is ozone. So, all that said, we need to be careful about removing foliage, especially in the inefficient artificial light we use. This is why plants shut down during dark periods. A molecule out the stomata in turn pulls a molecule in the roots....a chain of sorts. I gotta brush up on my terminology, second time today I can't remember the correct terms.