There was a serious wall at the tour of Hermann. About 0.2 mi. 2nd half was 25% or more. On the steepest part I hit a low of 3.8 mph at 39 rpm (after 30 hard miles). And there were plenty other riders going slower.

There's a brutal local climb I do here, 0.5 mi and the last hundred yards is 20+%. I hit low 50s rpm at about 5 - 5.5 mph - and I'm an ok climber. Hard to believe that Road America has something steeper. No indication of it on the elevation chart.

If there is a 28% then some riders will be falling sidewards. I saw one guy do so at Spring Prairie and he took out the race favorite.