Right now i am level a warlock (currently level 35) and i plan to level a death knight in between but what im asking is are proffs really mandatory? i mean i have pretty much all of them on one main/alt or another, and i just figured taking them while leveling will slow me down, but then if i do want one then when im 80 i have to re tread all the way back through old content, for something that makes a 'slight' different at 80?