That dump style of limiting the flash power does have one upside. It will give you a much shorter duration lowest power flash than a thyristor will. From my reading and experiments with a small strobonar it will fire at 1/50000 sec as opposed to a thyristors 1/20000 sec minimum. At least that was the situation back then.

This shot was taken with that setup:
http://www.apug.org/gallery/showphot...cat=500&page=2
I also got some pictures of exploding firecrackers and falling water droplets that were pretty interesting.