2003 NA Lightning champion Al Terhune:

"What made North Sails your choice of sailmaker for your Lightning and
what models did you use and why??

We use the Fisher MF-2, JF-2 and the R2 spinnakers. We use the Fisher
sails becuase we like knowing that our boat is always tuned properly for
the wind conditions. When we were starting our program we felt we were
better off getting speed through trim and sail adjustments then to try
to get our speed through rig tuning. We feel this set up is very
versatile and it gives us so much confidence that no matter how windy it
is we will be set up right and fast. The R-2 (spinnaker) is just plain
fast on all points of sail."

Look at that, he says his choice of a radial cut is good on all points
of sail. Obviously he must know less than our resident Lightning expert
Mr Doug King! Perhaps he should be told!

Cheers