I see very few people actually going for the 6637/6400 haste breakpoints, most of which I think are just testing it out. I would probably recommend going for 4717 and the rest into mastery, if you're over 490 ilvl it's probably time to start gemming/enchanting full mastery anyways. It's great that you can reach those breakpoints, but is it actually viable sacrificing mastery gems/enchants/leaving all your mastery in the dust for it? probably not, but always sim the different changes and see where you get.
Shameless bumb, excuse the noobness as I seem to be a bit behind on the haste break points. What exactly is the significance of the 4717 haste break point? I can't seem to find it on my spreadsheet of available breakpoints?
Thanks in advanced
*edit* Nevermind found the extra corruption tick under just raid haste. Answered my own question, nothing to see here.