Not really a madhouse. The morning, as a matter of fact, was quite nice. The crowds didn't start really building till after 11. We left before 4, and people were still coming in, so I do not doubt things got really tight.
In addition to Mercy, there were still several choirs there (reminding me of my own choir trips there, oh! so many years ago). As for behavior, the choir kids were angels compared to the Mercy adults. They seem to believe that the city is their own personal property that day, and they cut in line, block traffic, push past, and otherwise dominate the area, even when the crowds are light (as was the case in the morning). Mercy really needs to reflect on the image their people are giving of their institution.