I decided to take the Metro back from Tenleytown to see what would happen. In short, avoid it. Walking is probably faster. It took about 20 minutes for the train to show up at Tenleytown, then another 30 for it to get to Gallery Place, due to single-tracking along the way. Then about 15 minute wait at Gallery Place for the Green line, and then home. In all, it took about a hour and a half.
The Circulator bus is running, however, which I should have taken from Woodley Park. I saw one show up at the Columbia Heights Metro. Might be a better option.