It has been touched on, but I would reiterate that finding the wind and sailing the boat well are critical to going fast in the super light stuff. I very rarely change the way I rig my boat (Hobie 17). Possiby kick the windward rudder in the light stuff.
Having good wind indicators (VHS Tape) is very handy. I don't look at the tell tails on my sail too much, but I'll glance up at the top ones if the boat feels sluggish to see if the lee side is stalled. It's best to get a feel for the boat so you don't have to look at it (get your head out of the boat). I try to spend 2/3 of my time looking around for wind by watching the water and the speed and angle of other boats. When the wind is light, you can actually listen to the bow ripple and the flutter of the VCR tape to hear accelerations. Also, if you turn off the rachet on your main blocks you can more easily feel changes in pressure. I almost constantly adjust my mainsheet, one or two inches out in lulls and one or two inches in for puffs.
Just some suggestions.
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