Duotone says the S-1 and Blade are forward & up fwiw. This might also help?

BullroarerTook said..
Also, I remain unconvinced it's that important for foiling. At least on the sub-5 sails I usually use. Willing to be convinced however.

I use sub 5m sails too. I won't try to convince you but I personally find that having the draft between the hands makes thinks easier.

I forgot that Duotone had the info I was after on their website too. Thanks.

I don't know exactly what you mean, but my hands stay pretty much fixed in one spot on my boom when foiling. The draft of the sail does not move around so you don't really need to move your hands on the boom when foiling if your hooked into your harness. Some times I move my hands up and down the boom a bit when not hooked into my harness but I'm pretty sure this has nothing to do with the position of the sail draft. This is just me though. Others might do things differently.
Sails with a high and forward draft are "forward pully". Ie they have a forward pulling feel to them. Some people don't like this feel whether it be for finning or foiling, and some can't feel the forward pull. Again, as I mention above, having the draft central and low (between the hands) makes things easier. At least for me anyway. I find a forward and high draft can be awkward and make things difficult sometimes. At least with the sails I have used so far.