There is a mayseh brought down from the Vilna Gaon in which I think Reb Chaim Volozhin came to him and said he learned Masechta Sukka 14 times. The Gaon asked him how many times is Abaye mentioned, how many times is Rava mentioned? How many times is Sukka spelled with a vav, and how many times without.
He said the number of times with a vav was equal to the number of sukkos kesheiros in the mesechta; and the number without a vav was equal to the number of sukkos pesulos. (I also heard it may be the gematria of sukka with and without a vav that corresponds to the numbers of kesheiros and psulos.) I don’t know which is correct, or if I’m saying either of them right.