CO 34 DEN-LGW is very dangerous...check this out from CO.Com:
1 Stop. Time on the ground in Houston, TX (IAH - Intercontinental) is 47 minutes. Change Planes. Equipment changes in Houston, TX (IAH - Intercontinental) to a Boeing 777-200ER.
I always take an earlier DEN-IAH flight to allow plenty of time to make the connection. Yes, many of the direct flights are a bit of a joke.