Parry & Dodge - 4.0 - Whats' the point of 2 stats?

Historically there were major differences between dodge and parry

1. Per point in dodge you recieved more avoidance than parry
2. If you parried a mob, you risked parry gibe whilst dodge didn't making it more tasty
3. Parry and dodge are subject to diminishing returns and at certain odd points, parry could exceed dodge in avoidance.

Most tanks avoided parry if there was another avoidance option on the table, because parry gibe was just too risky, also because per point dodge was better. However sometimes parry was worth taking since 50 points in parry is better than say 10 in dodge.

In Cata parry gibe has been removed and parry raiting gives same avoidance% as dodge.

My question is what is the point of having 2 stats, that do exactly the same thing for the same ilvl cost? I don't like the way they have tamed down the stats and balancing but even I can't see the point of having 2 stats that do exactly the same thing.