meowenginer
It isint because the concept of dreadnaught is the largest possible vessel/class, your making a heavy dreadnaught that's rather redundant. More pressing is the class you've though up reasons for reason for existing, is to make a comparision to non heavies. The class is self nessesitating theirs no point, wow heavy dreadnaught cool that doesint tell me anything about the vessel besides it being heavier then the heaviest ship you have. A dreadnought, by definition (at least in sci-fi) is heavy, you can't have a light heavy thing it doesint work from a naming prospective nor logical prospective.
(On a side note this entire chat became semantics XD)