I've read this whole thread....ugh.
What it comes down to, in my opinion, is your grow room, strain, and personal preference. We all have our own "tricks" and "secret methods" for producing an optimal crop.
I, for instance, have recently tried the defoliate approach, Just because I've lurked so many forums arguing whether or not to do it. I can say that with my Northern Lights #5 it has seemed to improve growth in veg and in flower. I grow in a DWC system with GH 3 part nutes. I can honestly say that as of today, which is day 31 of flower, the plants that I defoliated are much more vigorous. Many more bud sites, and big white pistils reaching for my 600w HPS. The un-trimmed plants are good as well, but seem to be stretching and forming flowers a little slower. I'll try and get some pics up soon, and continue to report the grow.