I read a review the other day in which the critic posited the theory that Julian Fellowes likes his characters so much that he can't bear to see them come to harm. That may be true, in which case any amount of suspense about who will make it home from battle safely is removed. It's nice to see Edith and Mary turn into human beings, though - my theory after the first series was that they'd get into a knife fight with each other and both die of tetanus, but I think it's better the way it is.