Keep in mind we also have seen a Titan ground pound. So perhaps he gets space magic AND weapon proficiencies. Perhaps they all do. There was a thread a little while back where someone theorized that even though the warlock could use the thunderlord they noticed it had a pretty low rate of fire with for a machine gun. He went on to further speculate perhaps it required the strength of a Titan to use the weapon to its full potential. Deej commented with something along the lines of "I guess we will just have to wait and see" and posted a link to moreconsoles breakdown of the thunderlord. So there is that. Lets take it one step further...... A linear upgrade tree is kind of dumb for weapons that Bungie want is to make our own. Perhaps, in addition to wielding the weapon more effectively, another advantage of a correct class/weapon pairing is that more upgrade avenues become available. This would allow everyone to use every weapon, but not all things are created equal. As Deej said. I guess we'll just have to wait and see.