They have small SCRUM groups of developers getting squeezed to death to put out more work without bringing in additional resources.
Just my guess.
Would you settle for one less dungeon in MoP for new classic models
and if they said they couldnt do it with that little resources
Would you settle one less Tier of raiding.
I'm certain that a lot of players would really appreciate updated models, even if it's not something they think about every day. Transmogrification is such a hit because in RPG's, people love to customize their character. How we look is a pretty big deal, even to those not into role playing.
I totally appreciate the danger in 'changing' the look that people have got used to, but the distinction in quality was clear when Blood Elves/Dreanei came out, it was blown out of the water when Worgen/Goblins arrived, and I hate to think how far in the past we'll look when Pandaren arrive. Sooner or later it'll need to be done, and in my humble opinion, the sooner the better.
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