On Tuesday, February 16, 2016 at 4:20:33 PM UTC+3, Tango Whisky wrote:
An L/D of 5 on some part is better than an L/D of 0 on that part. Even if some other part has an L/D of 50. (provided you don't make that other part perform worse, of course)

Total lift is constant. So if you shift a part of the lift to some inefficient means, your overall performance will drop.

Incorrect, because total drag is not a constant.

If you can get, say, 1% of your lift from the fuselage without increasing the drag of the fuselage, then decreasing the lift needed from the wings by that 1% will decrease the induced drag from the wings by about the same 1%.