Wouldn't it be nice if baggage handling got a bit more automated, so that in a transfer situation it could be clearly demonstrated that (e.g.) BA transferred the bags to (e.g.) EI at a specific time, and therefore the fact that they got lost rests with (e.g.) EI. I can understand the current position where BA doesn't want to accept responsibility for what subsequent carriers do or don't do with interlined bags.

Pity the airlines can't get together and look at the bigger picture, and so benefit the customer.