The reason why the MH glaive is pretty good is because its a 2.8 speed weapon and as such Obliterate will hit harder due to DK abilities not being normalized to weapon speed. It's not much of a damage boost, but it is a damage boost.
I've been looking at going for a BiS Chain Heal spam resto shaman for maximum throughput on fights where it would be effective, and these are the things I've taken into consideration by choosing this set of gear and listing it as BiS.
CHARDEV (for some reason it won't let me put +81...