Dear Andrew,
Thank you for the kind words. I was thinking about it - - my reading I mean - - and it occurred to me that strangely enough it is because I have studied music that I was able to come up with it - - I have learned to listen for subtle repetitions. But of course the brilliance is Nabokov's.
The reason that I am tenacious is that working out the solution to the problem gave me so much pleasure following much frustration. I could not have known I was on the right path had I not taken VN's hints to read Dr Jekyll and Mr Hyde especially, but also The Portrait of Dorian Gray and The Three Faces of Eve because it was in the echoing of specific words from PF in those texts that I found confirmation.
By the way, I was disappointed to realize that Mathew Roth's student hadn't found the solution independently as I think there may be another route leading to the same place.
Carolyn