Two clews without a clue

Gestalt, just going on my own theory and experience - I went to look for my books but my beloved has "stored" them

Looks like we are mixing two variables - using different clew holes and adjusting the outhaul.

I completely agree that applying more outhaul puts the position of max draft further back as well as reducing the draft. Less draft is usually better for upwind performance and sometimes very light wind performance (to maintain the flow across the sail).

What I guessed about the upper clew hole is that the draft position is slightly forward compared to the bottom hole (all other things being equal).

I think (and this is probably the contentious bit) that if you could move the position of draft independent of the amount of draft (as you can on some boats) then you would move it forward for upwind performance. Draft point forward means less angle of attack and a direction of lift closer to the direction you are travelling in giving a better forward force. I'm curious to know if anyone can verify that coz I asked five people and got six different answers

I'm guessing that moving the clew hole is close to of altering the boom vang on a boat - lower hole less vang, higher hole more vang.