I genually get all that, and id be very surprised if anyone could make a totally flat resonance bass cab.
This is what my question was addressing. If its not flat or neutral why advertise it as such? Close to flat, relatively uncoloured etc, i get those sayings, but calling it FRFR does seem like a marketing thing if you arent actually getting a flat or neutral response cab. It seems like the phrase is used to encompass a variety of cabs that are less coloured than the mainstream, but still coloured enough that they sound different.