Might not be, might be. Awesome discussion we could have there, no doubt.
Mobs won't one shot me because players that just got to 80 and are now leaving northrend without running one single heroic or raid will need to be able to kill them.
It is not common for people to need to level the profession above the cap of a previous expansion to start farming mats. For example, you only needed 275 mining to mine fel iron from hellfire and only 350 to mine cobalt from howling fjord. If they maintain that logic, you can mine cataclysm stuff with 425 mining skill.