Re: D'deridex class Warbird vs Galaxy class
Yes, most sources say that the Galaxy class's mass is 4.5 million metric tons. They also say the Romulan warbird's mass is 4.3 million metric tons. No source says the Romulan warbird has greater mass than the Galaxy class. Therefore, there is no proof that the Romulan warbird has greater mass than the Galaxy class.
Unless those sources include someone that actually worked on the show, I'd say they don't really count.
"I had no idea you were so... formidable. " - Anan 7 to James T. Kirk, A Taste of Armageddon