RFS used to have an aerobatic team sponsored by a well known manufacturer of razor blades. Later, even after the sponsorship ceased, they still used callsigns "Sword" and " Blade". We sometimes flew 3 or 4 formation sorties a day and it wasn't unknown for the leader to use the wrong callsign, when across the ether would come the helpful advice, "Come on Blade (Sword), sharpen up!"
CB