There were so many good alternatives to avoid this problem! Once it was found that the randomly selected guy had a solid excuse not to be bumped -- a doctor needing to get to tend sick people, the pilot should have made the following announcement, "Hey, do my a favor. If anyone whats to drive from Chicago to Louisville (less than 300 miles) we will get you a nice rental car and give you a check for $1000 to boot!" I bet he would have gotten many takers -- especially nervous fliers. This was an easy problem to solve but the airline employees acted like they were not allowed to use creativity -- just follow the rules verbatim.
but this is all predicated on their attitude that the passengers are just cargo they can move around as they please. the process was void of any sense of human decency. why? because the airlines have been allowed to act like this for years.