winglets

It does matter. The pressure on the top side of the wing I a lot lower
that the surrounding air, the overpressure on the downside only a bit
higher. That way it makes sense.
For avery angle of attack (Cl) there is an optimum configuration,
usually a double eliptical shape. (Bend up like a Discus-2, a bit the
shape of an ls-6/8)
Alhoewel real life deals with Reynolds and sideslip whick makes is a
lot more complicated.

For the jetliners, a very small "extra" inverted winglet clearly lowers
the vortices. Also dependant of cruise Cl, Reynolds, mach number.

Jarno Nieuwenhuize
The Netherlands.