Question from a novice of sorts.
Why would the pilot go to Miami rather than Chicago (original destination)? Assuming he wanted a longer runway....ORD has at least the same length runways, no?
If there was no urgency to land (and in fact he took time to burn fuel), why not burn fuel going to his original destination? (I'm sure the fire trucks respond as well in Chicago....maybe the risk of drag?, maybe the risk of icing?)