I have tried all of the specs as a warlock and i am pushing out a good 10-15k more dps as a destro lock yet i see everyone saying affliction is the best. Now it may be my fault somewhere that those specs aren't pushing as much but i am curious as to what i might be doing wrong as destro right now, as i can only pull 30k on the stone guard and 42k on Feng. My character is Nekthelus on Illidan if anyone can look and see what i am doing wrong?
Destro is simply easier to play, it's much must easier to get Destro's spell priorities right. Affliction is only theoretically superior, in practice you need to use the spec that mosts suits your skill and prefered playstyle. I too always do better dps with Destruction. Although that may be because neither you or I have really learned and internalized Affliction's rotation and priorities.
Also different specs have different reforge priorities (you don;t technically need to be hit capped with Aff, but you absolutely must be hit capped as destro) and if you are not testing each spec with optimal reforges you might be getting scued data).
Unfortunately i cannot look up profiles, I hope someone else will give you more specific feed back.