Forget the signs on the route markers which read "Inner Loop" and "Outer Loop", just in case you don't understand the concept.
Forget the fact that the traffic reporters never seem to report on the backup that you're in until you're a mile past the spot where it cleared out. (And forget the fact that half of the backups have no clear reason for existing.)
No, the real woes of the Capital Beltway can be summed up by something that a Washington Post columnist, Bob Levey, wrote about it a couple of years ago: he rated driving the Beltway a worse experience than Highway One in Vietnam while under mortar attack and dodging land mines. Of course, these days, you have a small but measurable chance of having to dodge small-arms fire...