Blizzard abandoned the "slow" spec concept late in WoD beta. In fact they sped up the rotation three times, and twice again after launch. I wouldn't even call what is on Alpha now slow by any means, it's sitting comfortable at around 50-60 APM.
Obviously going too fast (Gladiator) is problematic, but inordinately slow rotations don't work any better. It simply isn't the type of gameplay that WoW is built around.