The key to LAX-FAT IMO is taking the late SkyWest jets in. When I was commuting the day time Brasilia flights could get pretty full (although misconnects were pretty frequent), but there was a 9 pm and an 11 pm flight that almost always had lots of seats open. Things will change a little bit for the better (for SkyWest commuters, obviously not AMR guys/gals) now because SkyWest will be doing the Eagle RJ flights midday, but there is still no shortage of competition for the jump. If you're willing to hit Denver or PHX, you shouldn't have a problem finding your way into FAT, although with the expansion of LA and SFO, I don't think one would be forced to stay in FAT all that long.