As soon as I read your post, I went and checked the position of the fin in respect of where I think I had my foot, you're right, it's just about on top of the leading edge at the front of the centre fin but not quite as far forward as the 2 outside fins.
I guess that makes perfect sense as to where the best place to turn is, doh, why didn't I think of that. Of course short boards have them way back, that's where their centre fins are.
I'll see if I can find one I like, most I saw today had a funny lump just in front of the tail block, I think I'd prefer it to just be dead flat.
thanks