Reply To: Single vs double hole tzitzit

there is a shita of the baal ha’ittur that tzitzis needs two holes. As you will recall, the gemarah tells us that kesher elyon is deoraysa, because otherwise the tzitzis is unattatched. According to the baal haittur there is a in-and-out even without a knot, which constitutes an attachment regarding shabbos. This is one of the reasons other rishonim argue with the baal haittur. As mentioned, chassidim generally follow this shita and litvaks do not.