Technically, the Valk and Zeus are strike bombers, an entirely different sub-class of bomber. They are designed to be quick bombers, and are the equivalent of the Artemis. The Boanerges can only be rightfully compared to the Medusa, which very-well may or may not be more maneuverable, but the fact that the Boanerges isn't noticably more maneuverable than the venerable old bird means that the tech-description is utter tosh.
That's not to say the tech-description are all complete tosh, but it does mean one should take all information given in the tech database with a grain of salt when making an assumption in the FS Universe. In-game chatter and command/tactical briefings were quite obviously scrutinized far more thoroughly, and hence can be better relied upon to hold steady as a strong reference.