Actually, I’m not coming back to this funny little idiom, I just thought the title was catchy and, if you are reading this, it would seem to have worked.
Of course, idioms like “back to back” cannot be analyzed but must be taken at face value (so to speak). However, I did try to imagine how eight episodes of “Murder She Wrote” could be shown “back to back” as was announced sometimes in the not too awfully distant past on some television channel I occasionally peruse.
As I visualized these episodes, the first would have to be played forward, the second backward for them to be shown back-to-back. This means that episode two and three would be shown face to face–if anyone was still watching after number two was shown backward. Episodes three and four could then be shown back to back again.
Of course, I should be writing this idiom with hyphens, “back-to-back”, as do the dictionaries. “Back to back” without hyphens would mean literally “back to back”, as to stand back to back before stepping off ten paces in a duel.
We could avoid all this confusion with another phrase, face to back, but no one seems to be using this expression. We need it. That is the way bands march and people sit in auditoriums. Why isn’t it around? Let’s start using it. That’ll teach them.