I'm generally an advocate of closing a section of line to work more efficiently, rather than spreading the work out over many nights/weekends, at least until the maintenance backlog is substantially cleared.
That being said, if this strategy were to be pursued, WMATA would need to run alternative bus service paralleling the route. I'd suggest that strategic intersections should also have police to direct traffic to provide priority to buses while this work is occurring.
Not providing replacement service has tremendous impacts, particularly for those without any alternatives, as this article indicates. Low income workers are also much more likely to work outside of typical 9-5 M-F hours - something that should be considered for those advocating that service should be suspended exclusively on nights/weekends to bring the system up to a state of good repair.
