Every few weeks 9W sends out email about "announcing new" codeshare from/to USA with Delta via AMS.

This has been happenning since Jan/Feb but fares offered under this codeshare remain completely non-competitive - usually highest among dozen or so airlines offerring serious fares on NYC(JFK or EWR) to India(BOM or DEL) route.

Any insiders have any background?

If you have to fly onward to secondary cities, single PNR for entire booking is basically essential due to the baggage policies of the domestic carriers (at least in Y).

How are pax handling this situation (other than using AI/EY/EK)?