re: barber hauler -- I wondered that too. Maybe that's what it is. I wonder if you get the sail out much with it rigged through the rear of the amas.
You get it out far enough to notice a definite improvement in downwind speed as the standard sail simply bellys and as a result is much reduced in area.
The "complex" style BH I use also allows more control of the sail foot by being able to haul the "virtual block" forward when the sail is partially furled.
can be tightened so it draws the double block forward and down, (This Photo), it is now similar to moving the Sheeting Block position forward a la RoadRunner's post, "Better Rigging For Your AI". viewtopic.php?f=32&t=4755
With this system you can, to an extent, alter the camber of the sail foot without changing the angle of the sail to the boat significantly and having to make the corresponding steering adjustment. You can see this in the attached image.
Sort of like a variable geometry wing
A popular and much simpler, cheaper and easier to operate BH is achieved by having a line of Bungee with a hook permanently attached to the AMA stern saddle which manually replaces the main sheet when downwind.
I don't find it complex as I like continually having things to do and like tweaking the max out of the boat, I have Six lines coming into the cockpit, wheeeee! ( And it makes me faster than the other AI in town
I don't use Pedals when sailing so everything just floats around in the Well, no prob.