Are there any congregations who follow the ancient (Eretz Yisrael minhag) triennial cycle today, and so complete the Torah once every three years? I'm aware there are some Eretz Yisrael minhag revivalists out there; is this among the practices being revived?
I heard from R. Nota Greenblatt (the eminent posek of Memphis and the greater South) that since the original enactment to read the Torah did not include the familiar rate of once a year, that in a case of need e.g. the baal korei has difficulty reading the whole parsha, then one could finish the Torah less frequently. He implied that one would not even need to adopt the other ancient custom of completing it every three years, but one could instead choose a pace.
See also here for a nice collection of sources, albeit from a non-Orthodox source.