This was offered as a solution to the Companion Pass and seat-saving problems, but it has other benefits, as well.

Check-in should be by PNR, not by individual. Persons on the same PNR get consecutive numbers at check in. So, if you want to do the most you can to ensure that you get seats together - short of buying BS for both or all - you book together on one PNR, and do OLCI (or whenever) in one fell swoop. The problems above are alleviated, and this form of the stress related to the old canard about "racing for seats" is reduced, if not eliminated. And it's very doubtful that this would materially take from the BS market, such as it is, IMO.

With all the enhancements recently made to the website, there is no remaining reason why this solution isn't possible.