I guess so, Ian - and even in this special case, the book's cover had to suggest a single story, which goes to reinforce what John said earlier about the market.
(May I admit here that I would probably not have bought the book if it had been presented as two stories; in this case, I'm glad I was "fooled"**.)
** - Not difficult to do in my case, it seems, as the Contents page gives the game away. (
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