[EDIT] But anyway, in reference to why Hunters without MS is a bad idea: Hunters synergize horribly with Warriors and Rogues. Neither offers very much control in the face of the things that screw over Hunters most, namely caster burst and caster CC. They are easily kited and easily CC'd, and once kited they cannot help the Hunter, nor can the Hunter help himself (although this has changed since TBC to an extent due to Deter and Roar).
Warlocks and Mages, on the other hand, work a lot better with Warriors and Rogues. Both have spammable CCs, Counterspells, and various ways to either keep themselves alive when their Kick/Pummeler has been CC'd or stop incoming damage without blowing offensive cooldowns on defensive purposes.
Exactly that's why we should be changed to be more like warriors/rogues so we compete against them for group spots while maintaining our ability to fullfil the role as a heal de-buff class and be competitive in the primary/hybrid/healer group configurations.