Originally Posted by swingspan
Yes, my BOS-LHR-BOS and LHR-EBB-LHR are two totally separate itineraries. My assumption is that checking bags through was not possible in that scenario.
I don't see why not - I have done that on a number of occasions. If you can show the reservation confirmation at checkin then it should be perfectly possible to tag your bags through to the destination, even if they can't issue the second boarding pass.