Over the last couple of months I've started defoliating, at first I removed very little, but recently I've been removing many leaves at a time, not complete defoliation (fans getting good light and not shading out the center or other buds), and also not on a set interval like day 1 or 20, but when I notice new fans have obstructed the interior or completely shading out side shoots which can be every 3 days, and i have to say I'm really liking growth a lot.
This is being done on some clones I've flowered and harvested at least twice so far.
I've gotten pretty deep into gardening over the years, and I general plants do better with environmental stressers, like cows grazing grass improves growth, and it seems to reason with our limited light penetration from even the best of lights, that the combination of controlled stress from defoliation and the increased light reaching all the buds sites that you'll get better growth, and better doesn't necessarily mean more yield, but better medicine overall