Wrong.
And not to attack this sentiment (I know where you are coming from), but since TBC/WotLK, we've actively stated our goal was to get the length between expansions down to one-a-year as our way of combating a lack of content
http://us.battle.net/forums/en/wow/t...6000?page=3#56
WoD was effected the worst because they grew the WoW team significantly and a large part of WoD was spent training and bringing developers up to speed with the product. You can't just plop a developer into one of the largest codebases in the world and expect them to instantly be at 100%, hence when they moved onto the next expac at the slowed rate WoD was left with nothing.
However all previous expansions were effected by this same goal, from TBC (Black Temple was supposed to be the last raid instance) to WOTLK (ICC was supposed to be the last raid) to we all know how the previous expansions have gone.