Second that. The elimination of JFK-IAD makes it impossible for me to experience the PS flights...
Technically (and unless they've changed the routing rules), you should be able to fly into LGA and catch the bus or a cab over to JFK (or v-v).
Pain in the butt, but I have done it several times when the nearest IAD-JFK flight was nearly sold out (and the later ones broke the 4 hour connection rule).
I think those of us who flew p.s. out of the WAS area via this flight were very few; it's more IMHO about the *A connections they're closing off.