Yes,

Basically it is a three stage cascaded setup.

First stage (blue line) is a 2:1 with a nice soft 5 mm swiftcord line or something. You'll be holding this line in your hand.

The second stage (red line) is a small diameter and very flexible high tension line like 2 mm D12 or 3 mm dyneema. The purchase here is 3:1 making the total internal setup a 6:1

The third stage (green line) is a 2:1 system with a 4 mm dyneema line with a tough outer mantle. This is needed as it does rub against the goose neck or other components a little bit. And it is out in the elements (UV radiation etc).

The internal 6:1 setup followed by the outward 2:1 setup make for a 12:1 setup overall. By using the different line diameters this setup is cheaper and runs more smoothly then any other downhaul setup. This is especially so since most of it is inside the mast and thus well protected from weathering and salt.

Wouter