nope.. defoliation is a self-inflicted need, if needed at all. If you don't over-crowd, never need to remove mass amounts of leaves.. should always avoid that if possible.
if you think some areas are congested and concerned about infection, go ahead and remove a few select leaves.. don't create holes in your canopy. bud sites do not need direct light.. never favor a bud site over a leaf absorbing light. apical dominance dictates what grows densely vs larf. I regularly leave buds covered up and they never look different than other equivalent buds on the plant. again, direct touching and 'suffocating' of leaves of buds would be a bad thing in extreme cases. Buds that are pushed up against each other often lose their color at point of ocntact etc and prone to disease. apply common sense in those situations...
with a well-managed canopy, proper light penetration happens on its own. needing to prun a ton of shit off just means you wasted a lot of electricity, time and fertilizer.