The codex does seem to have a number of ways to generate mortal wounds, then there is Mortarion.. thats just utter filth.. excuse the pun.. but high T, with 3+/4++ and then 5+ per wound, then their is the cc attacks, then Mortal Wounds for each unit within 7", the list of stuff just gets piled on...
new dex, new over the top rules to encourage people to buy the new insanely priced model... that 7th edition smell seems to be coming back.