I've always had the notion that the original Stewart Style dries fish in much the same way as our more modern emerger style patterns, i.e. with the hook below the surface half in / half out trapped style.
So if you put the wing directly out the front of the hook it would then fish straight up as the hook point would inevitably be submerged.
I know this wasn't how these flies were originally designed to fish, however I'm certain that they did and were to downfall of many a fish as a direct result.
