That would be hard to say as factual. And perhaps the dread may not out dps the excel, but it is unlikely the excel can do more than the dread either. Assuming the exact same weapon build, the lance gives about the same amount of extra dmg as the Lt com/Lt slots do in a 3 min time frame. But to maximize dps, you would never use the weapon load between the 2 ships.
For example, in pve the dread can use DHC effectly, which allows it to out dps the excel. In pvp, DHC is useless, and you would need a different setup. So at best, one can say that the 2 ships can do roughly the same amount of overall dmg.
Lastly, if they really do allow saucer seperation later on, making DHC viable in all aspect of the game, the dread will definately out perform the excel in dps. So I still stand by what I said, that I can do more dmg with a dread than most can in an excel, depending on circumstance.
I do see this all the time, people saying that the exta tac boff power makes all that much of a difference, in reality its not an extra tac boff, its just an upgrade boff, because the GX still has the Ensign. and when a wwell speced GX can pull over 500DPS from the Lance ALONE, the excel cant keep up.