We just finished the 17/18/Tiger event in Harrison in august.... we put in the SI's 'maximum of 20 races will be run'... 3 days we had four, 1 day three and one day 5 races... we were fortunate to have windy conditions for the whole week.. double trapped every day for some parts of each race... also a few big holes of no wind in the water.. i found a few.. unfortunately we had rain everyday as well... except the sun came out for the awards banquet.. (and it's been shining ever since.... )
My point being.. 20 races over 5 days seemed like a good number.... but their should probably be a maximum of 5 races in a day... regardless of past/present/future weather conditions... 5 hours on the water without a break is plenty... and keeps most people able to race the next day.