How good we are shouldn't come into a discussion about the class so i wouldn't sweat it dude.
Even so, with three fast staggering blow combos (even without bone shatter) Upheavel will do more damage with reverse swing up than it will from the points into butcher upgrade ^^
I 99.9% time use AtG not bone shatter... But i always upgrade reverse swing and hammer and anvil as with those up the staggering blow combos become powerful 1-steppers staggering blow 3 crits over 3k fully feated and it's fast onestepper.
Point is, even not using the AA-Staggering blow bone shatter the reverse swing +36% weapon damage will boost your upheavel (and ALL other white hits and ALL other damage abilities EVERYTHING )
That was all the point was. The staggering blow combos are only worth doing to get reverse swing, and they are only worth using for doing ANY form of damage they need hammer and anvil.
The staggering blow combos are pretty much pointless without those feats, which imo is stupid. If they had a worthwhile debuff effect it'd be different. But they don't they have negligable hit rating debuff that does NOTHING at all EVER.
Hope that explains what I meant, but it is ONLY my opinion.