Looking at so many of these perennial contender teams is somewhat of a cautionary tale, there are some HOLES on that Caps team.
It's a reminder that you have to be willing to move on from non-core pieces while you can still get good value in return for them. Keep the pipeline flowing and such.
Also, you have to be careful with picking up expensive rental players/avoid it. The teams that win the Cup tend not to be the ones that pick up the biggest names at the deadline (some exceptions, obviously, but in general).