Originally Posted by
Taoyuan
And obviously if you get re-routed for whatever reason, not only would your plan fall apart, but your friend would presumably be left scrambling.
That's a real risk, especially this time of year. Chicago often has weather problems that won't affect a non-stop flight from PIT to MIA, or flights via other hubs (e.g., Atlanta) in a southeasterly direction. Whoever sold you the ticket promised to get you to Miami, not to let you walk around O'Hare for a while. It can cost you a lot more to get back to Chicago from Miami, or from any other connection point, at the last minute than you save via this method - to say nothing of how many hours you'd waste in the process.