Well, do keep in mind the origins of the Metro itself- I've talked with older residents in DC who remember when Metro was being built people were terrified it'd bring the problems of the inner city out to the suburbs; remember that it was being planned/built in the late 60s/early 70s when DC was a much more violent and scary city than it is today. This is what led to the system being inefficient and weirdly laid out in the first place.