I thought the Sail Calculator site used Rod Johnstone's equations to calculate motion comfort but they don't line up with what I can see on that chart. Here are the numbers for an Alberg 35 and Tripp 33. Your chart shows the Alberg 35 at 26.47 vs. 36.48 from the Sail Calculator and the Tripp 33 is 28.96 vs. 14.09 from the Sail Calculator. Maybe I'm just reading your chart wrong but it seems strange the Tripp would have a higher value than the Alberg.