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I have no idea how well that would work, but I can see how for readers who are fans of the series it might be a way too keep interest alive as they're waiting for the next book. For more casual readers, it doubt it will really do much.
Either way, it's not something I've seen done before and that in itself means it might be worth trying if it doesn't require too much effort on your part. Some marketing/publicity gimmicks work only if you're among the first to use it.