I was always told to never warm my BMWs up. Just drive them conservatively (under 3000 RPM) until the car is warmed up. That's because fuel is richest (supposedly) at start up. The ring seal has not expanded (too cold), so it allows moisture (fuel) to get into the oil.
Also, short trips make for other, possible oil issues. Something about oil and water evaporation (not taking place).
I understand why short trips suck. The car never really does get enough time to burn off any moisture that may have been left in the system since your last drive. That goes for exhaust moisture too.
If you can take longer trips to work that might be a good idea, JB. Also, be sure the car does get some longer trips -- perhaps on the weekend. Finally, be sure to change your oil more often if you're doing all of these short trips.
Hopefully my post will spawn some chatter on the subject. I know enough to be dangerous. The more mechanically inclined will likely clean up my explanation.