Nope, I'm not talking about hordes in BI, but regular factions in vanilla RTW. I've seen a guide for Germania that advocates abandoning the home provinces, and then swoop down and settle in Italy.

I'm sure that's possible, viable even, with other factions. For example, is it a viable strategy to throw everything at Egypt and settle there as the Seleucids? Is it a good idea to move out of Sicily and Campania to Asia Minor as the Scipii?

What are your thoughts on faction migrations?