Being in Phoenix I think about the short trip question fairly often, I'm not sure that really exists in areas like mine, or FL, TX, etc, especially if the car is garaged. In the summer my cold start is approx 90 degrees, in the winter it's probably 65. I don't have an oil temp gauge on my RAV4 but at morning startup my coolant is up to temp within a half mile, so I wouldn't be surprised if by oil was up to temp within a mile, esp if I hit a light or 2. Once up to temp, I can park for a couple hours and come back and the engine is still almost at full op temp according to the gauge.
So anyway, it doesn't seem it would take much to boil off any fuel or water. Maybe I'm wrong about how much longer it takes to get oil temp vs water temp.