Book of Plays

Joseph Hunter mentioned that Bliss had drawn his attention to them in the summer of 1832, and Black noted them on a proof-sheet of his catalogue of the Ashmole manuscripts.

[3] The description of MacBeth mentions characters "Ridinge", a detail that critics with a knowledge of Jacobean dramaturgy and stagecraft had found startling,[4] although subsequent scholars, commenting on a horse evidently present on stage in another play, have opined that it is within the realm of possibility.

[5] Also the idea that Forman, a worldly-wise and canny operator, would spend his time drawing sententious morals from the stage plays he saw struck some modern critics as psychologically false, and in the 20th century suspicion emerged that the Book of Plays was one of John Payne Collier's forgeries, although Collier, who announced his discovery of the document in 1836, claimed to have used a transcription made for him by an unnamed "gentleman" (identified in 1841 by James Halliwell as William H. Black, who catalogued the Ashmolean Collection).

In 1945, W. W. Greg criticised Tannenbaum's scholarship and J. Dover Wilson and R. W. Hunt both examined the manuscript without finding any evidence of tampering.

It was also learned that Tannenbaum, who had not examined the manuscript but relied instead on photostats, had compared the section with writing Forman had done ten years earlier instead of using a control from the same period.