I agree with you. A backpack beats everything else hands-down, especially with an urban multimode commute. Some mornings I cycle to a hovercraft or hovercraft to a bicycle. Some mornings, I ride one bike to a train, switch to subway and then to a train and back to another bicycle. It's tight on the subway and I want use of both of the hands/arms. I had a once every five day commute that when (cycle ... train ... airport ... plane ... airport ... subway ... bicycle) ... why would I want a pannier ... ugh

Hovercraft that gets used on some of my commutes (the terminal has bike storage inside!):