Roger,

Thanks for the explanation, it now makes perfect sense.  For a racer, I can see how maximizing the distance between the outboard end of the pole and the centerline of the boat can be important.  As a lackadaisical cruiser, if I’ve worked out the geometry correctly (which is an exercise I haven’t attempted in a long while), I don’t think I’m going to spend much time worrying about the fact that the inboard end of my whisker pole is now in a fixed position.  According to my calculations, if the mast end of the whisker pole is 6” off from its theoretically perfect position, the effective length of the pole is reduced by a bit less than an inch.  

Thanks again.  I hope you get to do some sailing this year ... somewhere.

—Peter

> On May 27, 2020, at 11:33 PM, ROGER PIHLAJA <roger_pihlaja at msn.com> wrote:
> 
> Peter,
> 
> The downwind sail is the spinnaker or genoa that is poled out, i.e. a spinnaker or genoa/whisker pole combination that is only used on a downwind point of sail.  On a run, any sail behaves more like a parachute vs. a wing.  Projected sail area presented to the wind is the most important factor.  It’s trigonometry, having the pole horizontal causes the clew of the sail to stick out further than any other possible orientation, thus maximizing projected area.
> 
> Roger Pihlaja
> S/V Dynamic Equilibrium