On Tuesday, July 29, 2014 10:25:28 AM UTC-4, Tony wrote:
If the handicap range is wide there is really no choice on a TAT other than large circles.and the handicap range doesn't have to be terribly wide to produce a wide variation on speeds achieved. On a good long soaring day that drives the requirement for a wide range between minimum and maximum distance

Not true Tony.
Add another turn area and the size of the cylinders drops significantly.
This allows the variability in task length without using cylinders that are 30 miles in radius.
I prefer cylinders of 10 to 15 mile radius maximum in part because this allows the pilot to see enough of the usable area to make decisions.
4 turn areas seem to work well for this.
UH