I jumped on this for a trip next summer, but BE fares around $2k are available in the spring and summer.
Routing I selected was DCA-JFK-MAD-JFK-DCA.
I used Google to find the date combos:
https://www.google.com/flights/#sear...015-04-25;sc=b
It's much easier than searching on DL's website. Once you find the fare you click on the DL fare and it opens the itinerary on DL's website.
I thought $2k for the BE ticket (767-400) was pretty good.
I found JFK-MAD for the same dates in BE for $1809!
Coach for the same flights is around $1100-1200.