Here, Fallows suggests that the emender
was also a professional musician, and because this was one of the last pieces copied into the manuscript, the emendations could have been done at any time, even after the manuscript ceased to be used.
Whether or not Hopkins had taken the trouble to consult this Oxford edition, or whether he had looked at Johnson and Steevens' edition of 1772, which reprints Warburton's caveat, he was still committing what Warburton, a notoriou s emender
, had regarded as the purist's error of restoring what had never been there.
The work on this piece continued well after the Birmingham Festival: the overwhelming success of the 1846 performance did not prevent Mendelssohn--who was a chronic emender
of his scores--from substantially recomposing sections of it before publication.