It will obviously be the turning point in the season if they make a run (Charlie included).
At the same time, it was already a pretty good, if flawed team. It could also go bad again quickly. Things looked just as good, IMO, after the home split against the Dodgers (another walk-off win) followed by two series wins.
They mostly control their own destiny, in that they can keep the Mets at bay, and take care of the Nats themselves. But they also can't be losing games they shouldn't (like against the Marlins).
And they'll still probably lose to the Dodgers in four, but would be fun to find out.