I think everyone here understand what "Dump Stat" means, it's basically a stat so worthless you won't invest any points into it. In WoW terms, it means we avoid equipment with that particular stat like a plague, unless it's on a crucial piece of Set Equipment.
It's okay (And necessary) that some stat is better than the others, but for some classes, this is taken too extreme. Haste on Sin/Sub Rogue is one example, my Rogue's Mastery/Crit/Ver sims between 22-30dps per point, and haste at...10.7dps per point. It's so extreme that I am still using my 900 Crafted Ring on my Rogue, because the 945 one I have is a haste ring.
It's not just Rogue either, Fury Warrior and Crit is another example. My fury warrior's Haste sims at 36dps per point, while Crit at...13.4dps per point.
I am pretty sure there're other classes with similar situation, but I don't have accurate data because I don't play them.
Do you think it's a good design that Dump Stat can go so extreme? I personally enjoy stat weight between 70% of each other (Arms Warrior, for instance), so that most of time, an upgrade is actually an upgrade instead of having to having to stick to much lower ilvl equipment (Not counting Unstable Arcanocrystal ofc).