Probably the same graphical limitation that:

-keeps my capes floating way above my draeneis' tails or just straight out on other characters
-has my orc and draenei's braids clipping and passing through their capes
-make long weapons pass through the user's body
-makes any squishy on a mount look physically impossible (fer craps sake it's called side-saddle. or hike it up and deal)

It seems to be a problem of having two flexible layers of cloth showing somewhere at the same time. They just don't interact well. Similarly in Champions, one of my characters wears a long trenchcoat and the cloth engine is so screwy the tails get caught and clip at the knees, through his pants, at a 90 degree angle.

I imagine it's an issue that the lower part of the tabard wouldn't 'collide' with the robe and result in a mess when running and having the lower part of the tabard clipping in and out of the robe while in motion

An example being cloaks clipping through weapons and sometimes the characters legs if the players character is performing specific animations. (A long cape on my Nelf will cut through his legs when it waves back and fourth when I'm casting a spell._


But yeah more than likely a system limitation where it's just easier and neater to just tuck in the tabard. Same with dwarves when wearing most helmets where the beard is normally cut off instead of having the hair coming out everwhere.

They don't necessarily need two flexible surfaces displaying and clipping, they could just paint the tabard's texture over top of the other texture being displayed on the "skirt layer" of the model. I'm glossing over details here, though -- what if the "skirt" currently displayed has an alpha mask that would cut out parts of the tabbard, for example? You need to "or" the two masks. Not hard, but just an example of how this isn't necessarily as straightforward as I first stated. I imagine they just didn't design it to work that way to begin with, and just don't consider it worthwhile to spend the time to make it work, it possible but not necessarily trivial to implement, and they have bigger fish to fry...

One of the reasons wow needs a serious graphical overhaul. Some of the animations are seriously outdated. We have better collision detection these days and some character models are in serious need of a major overhaul, Humans being the prime example here. It still looks like they crapped their pants when they run.

- So yeah, updated animations, such as riding on a horse... it just looks wooden, certain spell casting animations, running animations etc.

- Updated character models and an option to acually model a model. Some characters only have like three options for a category... you can't adjust the parameters either. Aion does a good job of customization, which I find lacking in WoW. It really should be a broader aspect. We're very limited, in my opinion.
Anyway, Humans particularly look bad. Bad model, bad animations. Trolls have very few options to change looks as well. Vanilla WoW models need updates, desperately.

- Also, updated collision detection. Swords going throug capes, tabards tucked in, haircuts cut off when wearing helmets. I can understand some collisions failures, but it is like they're not even trying.

I am not saying WoW should look like Aion, or FF XIV, but the game is several years old now. An upgraded graphical system would be nice for Vanilla WoW. Sure, WotLK upgraded spell animations and NPC models quite a lot, as well as having great design overall, but the humans still looked poor. Riding a horse still looked wooden and swords still sliced through capes like it was butter. WoW needs a major graphical overhaul in terms of character design, customization, animation and collision detection. Seriously, WoW is almost 6 years old.

i would like them to bring back tunics for casters, there used to be some, but now we all wear dresses. whats the point of pants having graphics if we never see them. i'm surprised blizz hasn't made the emperors new pants, a pair of invisible pants with awesome stats

Don't forget:

The horrible male troll belt that jogs up and down in two separate pieces whenever they move. I don't know what is worse, that or their cardboard cape.

Female orc's tabards always clipping through one leg in the front.

Female undead tabards that clip through the legs in the rear.

Male orc's shoulders that clip through their body all the time, then pass through each other when they jump.

Male undead shoulders that hover a foot above their body.

@ Piisuke

A complete graphic overhaul of character models is one thing that I absolutely wish Blizzard had included in this expansion. I wish that we had SOME kind of character customization that mattered on models that do not look like crap, compared to what is out there now in terms of graphic quality. Call me a party pooper, but I honestly would have preferred Blizzard had spent their time and resources for those sorts of changes than completely revamping everyone's talents, spells and stats. Let me test my skill AS IT IS against a tougher, changed world and let me look the way I want while doing it. Too much to ask, I know.

Updated character models would be awesome, except for the fact that people get very attached to the particular way their character looks. So Blizz could work like mad to improve things, only to be greeted with outrage when they're done. Doesn't sound a great incentive to spend the development resources - at least until people start actively quitting over the way it looks.

"Also, updated collision detection. Swords going throug capes, tabards tucked in, haircuts cut off when wearing helmets. I can understand some collisions failures, but it is like they're not even trying."

It's because they're not.

Blizzard simply can't afford to use a real-time cloth or collision detection engine because most people's computers can't handle the extra workload that would place on their processors, especially in places that are already laggy such as Dalaran and Wintergrasp.

So Blizzard resorts to using static animations for basically everything. Using a static animation that can't interact with and doesn't need to know anything about it's surroundings takes a massive load off of your cpu. Not counting the few exceptions, the animations do actually look realistic - take Night Elves, for example.

I'm not saying that Blizzard doesn't need to update the animations that don't look convincing. I am saying that they cannot and will not use a real-time animation engine, because computers today simply do not have the resources to handle such intensive tasks.

Maybe in 5 to 10 years. But not any time soon.