If you take into account the limited lifetime of autos and in turn the relatively little foliage they have, which IS the primary source of energy of the plants (glucose production), then I'd say pinching out leaves from autos is pretty bad. "short lives" should be an incentive to not remove any foliage, not a reason to. Another reason, unlike weak lower stems/buds, leaves do not use any energy from the plant. Unless a leaf is damaged, or something of the sort, I wouldn't remove it. The way I see it.