The ratchet adds drag to the line holding power. I can't imagine the need to have two ratchet sheaves. Too much drag possibly. You also risk having the ratchets on or off at differing times. I would rather have control over when they are on or off.

Hobie cat has used a variety of lines over the years. Curently the lines are Marlow:

<Excel Marstron is the perfect lightweight floating mainsheet for small dinghies. Excel Marstron has a braided core and smooth profile 16 plait cover of non-water absorbing floating Marstron. The smooth cover provides greater feel and faster running through blocks.>>

8mm Mainsheet and 6mm Jib Sheet.