I'm confident the 77W is driving greater paid premium sales on EWR-SFO... on one flight I took recently, there were no P fares for sale, but once I was presented with a $299 buy-up offer (which approximated a P fare) I jumped. Normally I won't do that for a TCON unless it's PQD-earning, but in this case I did it for the novelty of the Polaris seat.