I did a try.
I'm mainly 5boxing and i've got 16Go Ram, so i create a Direct IO ramdisk with Primo Standard.
I move the same MPQ than danji and i create link with :
mklink "S:\wow\wow\Data\world.MPQ" "Z:\world.MPQ"
mklink "S:\wow\wow\Data\texture.MPQ" "Z:\texture.MPQ"
mklink "S:\wow\wow\Data\itemtexture.MPQ" "Z:\itemtexture.MPQ"
mklink "S:\wow\wow\Data\model.MPQ" "Z:\model.MPQ"

But i've got some intensive cpu usage the game is far from playable.