Rolf,
Just wondering if you had measured the amount the distance between the bows of your Tornado would decrease when the forestay was loaded right up.

Just looking a 1 possible perceived advantage of running the pole lower when chasing the last poofteenth of a percent apart from the spinnaker.

The more induced tow in that you get when loaded the more the lower bridles that centre the middle of the pole and therefore tac of the jib slacken or loose tension.

This may affect the shape of the bottom of the jib as the luff may tend to get a kink in it with apex at the forestay, compression strut and bridle intersection.

Interestingly the lower the pole the lower the angle of the lower bridles to the mid pole and the less the lower bridle wires slacken with any given tow in so the better the bottom of the jib will hold its shape. This is assuming the Marstrom Tornado hulls are like other boats and give some toe in when fully loaded. I hear they are now running 15:1 main sheet so this may have started to become a problem.
No doubt there are many other influencing factors and the differences I'm talking about are so small I think we really need the guys who started the trend to spill the beans.

Regards,
Phill