The Nats may have managed to turn the OF situation into a mess yet again, but that doesn't hold true with the rest of the team. For once, the Nats are seemingly doing talent evaluation the right way and are letting Ian Desmond, Danny Espinosa, and Wilson Ramos have multiple months, not weeks, to find their footing in the majors.
Desmond has started 35 of 41 games this year, Espinosa 39. Ramos has only started 24 but has started 14 of 21 games since April 25th, clearly being treated as the #1 catcher. It must be tempting to replace all of these guys. None of these guys are hitting well.
Desmond : .217 /.255 /.362
Espinosa : .196 / .296 / .377
Ramos : .270 /.340 /.416
Despite those numbers I have a hard time finding a compelling reason to send these guys back down to AAA. Desmond has over 800 major league plate appearances. It's hard to believe that a short stint in Syracuse would enable to fix his issues hitting major league pitching. Espinosa is showing good power and patience, his problem is getting the ball in play which is what everyone knew his problem would be. Going down to AAA would change nothing. Ramos' is young for a starting catcher, but his minor league progression indicates someone with very little left to learn in the minors about hitting.
Of course it helps that the MI situation is terrible in the minors. The only player worth talking about in AA or AAA is Steve Lombardozzi and he's really just doing OK, not pressing for a promotion to the bigs. The catcher situation is a little tougher, but we all know Pudge is not going to be a starter for the mythical playoff challenging 2013 Nats, and Derek Norris is only just starting to get hot again in the minors (.405 / .556 / .960 in his last 10 games). He can simmer a little bit more (and maybe play some first base?)
It takes time for players to develop. We all know about Jayson Werth's slow rise to fame. Pudge didn't establish himself as an above average hitter until he had 2500 PAs (that's right 2500 - it helps when you start as a 19 year old). Adam LaRoche, a consistently decent hitter even as a rookie, was putting up a .250 / .292 / .388 line at the All-Star break his first year. With no good argument on starting someone else then it only makes sense to keep playing these guys like the Nats have, do it for the whole year, and let them either sink or swim.