The stat priority seems logical, altho I'd question the wisdom of going to the full 15% expertize cap and prioritizing mastery (armor) over haste (rage) for magical damage/bleed type of encounter.
15% exp cap, from a Rage per second pov you get a 7.5% better chance (compared to the 7.5% dodge cap) for your white melee swings to connect. This rating doesn't help your yellow damage (mangle!) chance to land or their crit (mangle->rage) potential, I may be wrong but I'd rather have those rating points turned into crit instead to also help on fights with adds and with misc dps tasks. Also it may be higher rage per second to have the 7.5% extra expertize rating points above dodge cap turned into crit
The way I'd see it it should be something like: 7.5% Hit > Full Blown Crit > 7.5% Exp> Haste > Mastery >= Dodge > 15% exp
Maybe I ought to hack TheeTova's spreadsheet a bit to do a double check on this