Only done it once, forced into it from Poly not having all the nights we wanted, and that cured us of split stays. We saw no advantage in doing a split, lived out of the suitcase for 3 nights, move day gave luggage to bell services and didn't see them until way after 3 pm same day. We never stay in a park opening to close but like to come back to the resort and dip in the pool, have a picnic lunch, change clothes, shower and plain relax. Being roomless on moving day is awful, you basically have to stay in a park, too sweaty and tiring for us or hang around the resort lobby waiting for your room, which can be quite a wait, and then waiting on your luggage.
We like to stash our stuff, set up our room to our liking, put groceries away and get the drinks chilling and just relax for the duration. We've been to WDW 40 times and we've got our resort down to where we want to stay, no more resort testing we've been to most and we prefer location and price so we know where we're going. Others like the split but we just not fond of them, To each their own.