ORIGINAL: HighPlains
I don't think that ultra thin trailing edges buys you very much in terms of drag reduction. The air has gone completely turbulent long before you even get to the hinge line, let alone the trailing edge.
Tell that to Selig et al after they saw results supporting sharp TE's in their wind tunnel work.
Turbulent separation bubbles and a turbulent boundry layer are two animals of different stripes. A turbulent boundry layer is extremely thin and any sort of obvious bluntness to the TE is going to be bigger than the layer. Also the turbulent boundry layer is moving with the airflow and if it falls off into a blunt area it'll form a typical bubble that adds drag.
Granted only the most fussy of sailplane fliers or extreme speed model fliers is going to see the difference but when you're talking about that last fraction of a % to gain first place it counts.