OK, I see you point(s) about the wing being "dirtied up" by slats, spoilers, etc; however, if the wing is a normally shaped wing, then it still looks like the driveshafts are still exposed under the wing. If so, I would think that laminar airflow characteristics under the wing would be different, i.e, lift is degraded. What am I missing here?
OK, now your picture came through and I now see the bottom of the wing with no driveshaft visible. No problem. Thanks for the visual.