It may look a bit crude, but a model train-set can show how Metro could get around a line closure for some months. Simply, get the local government (probably Arlington or DC) to reserve a lane only for buses, at least during business hours, and run enough double-buses continuously for the load, and cycle the traffic lights. Have the express buses stop only at Metro stations. Run 24x7 for people who work non-normal hours or reverse commute, and to help businesses.
We still haven’t been told specifically what maintenance needs to be done, but it seems a lot of it has to do with the power distribution itself.
editorial Friday calls Metro’s “threat” an “insult to riders.”