Negative 19 Minute Connection Confuses United.com

I made a negative 19 minute connection in Houston this week.  My flight from EWR was 37 minutes early and the next flight to Denver was a 4 minute jog away.  Even with the lackadaisical nature of people deplaning in front of me, I made it to the Denver flight before the paperwork was finished.  I was added to the flight in seat 2A; happily a first class passenger didn't make it and his seat hadn't been filled by someone else.  I saw on United.com that their IT didn't quite know how to show a negative connection time.

Yes, I Did Make This Connection