I also have a separate issue:
Based on my wife's nationality, she requires an airport transit visa for UK, IF the bags are NOT through checked from DEL all the way to JFK. I am hoping that my bags will be through checked, but in the event that check-in staff at Delhi don't allow it (remember when I called the BA customer service number today the rep. first said that they don't thorough check and even checked with his/her supervisor and, when I insisted on speaking to his/her supervisor and going over the rule, it was only then that he backed down. I can easily see the Delhi check in staff not backing down if they are not used to a BA-Virgin through baggage, in which case it would cause major problems because it would be a difference between getting a transit visa or not.
Second, in December, flights could get delayed either at London (snow, impacting the incoming flight to DEL) or Delhi (major fog problem at that time of the year. Let's assume the DEL-LHR is delayed and I can no longer make the connection. Who rebooks me on the connecting flight? Since British Airways presumably wasn't paid for the second segment (LHR-JFK), why would they take responsibility? And, if, because of the delay, they only issue a ticket to London, and ask me to get the boarding pass/ticket for the connection at London, my wife will be stuck because in that situation she doesn't have a UK visa and the bags are only tagged to London. I know this is hypothetical but I like to plan for all situations. (For instance, who would have thought that Virgin would cancel flights at random on 4 days over a 4 month period, and one of those days would be my day of travel!) That's why I like to plan for all eventualities.
Thanks for your patience in reading through this.