I thought that this was going to be one stupid idea, but checking on Wookipedia it's a completely different stupid idea: five pilots in five different types of starfighter. It would be one thing if it was something like four regular X-wings and a "Wild Weasel" fighter-bomber where the heterogeneous squadron composition provided some specific tactical advantage, but sticking a B-wing in a squadron with faster, more maneuverable starfighters means the entire element is reduced to the speed and maneuverability of the B-wing.