Authors:

If Shakespeare had to go on an author tour to promote Romeo and Juliet, he never would have written Macbeth.

"The Shakespeare Book of Lists : The Ultimate Guide to the Bard, His Plays, and How They'Ve Been Interpreted (And Misinterpreted) Through the Ages". Book by Michael Lomonico, 2001.
If Shakespeare had to go on an author tour to promote Romeo and Juliet, he never would have written Macbeth.