Geographic federalism might apply and work in very large countries, where the citizens belong to, more or less, the same ethno-cultural groups.
The USA, Canada, Brazil could be given as examples.
In countries that have different rooted ethno-cultural backgrounds, the ethno-federalism is a better solution (Switzerland, Germany, Belgium).
Lebanon is closer to the latter group in terms of cultural diversity hence the need to avoid Geographic federalism as it might lead to minorities being oppressed by the local majorities.
Geographic federalism with the regime of Qaimaqamiyatayn was experienced in Lebanon between 1943 and 1860. It was a disaster. It resulted in oppressed enclaved minorities and wars.
