Inthesummerof2015,legendarymusicianDavidByrnestagedanunprecedentedeventatBrooklyn’sBarclaysCentertocelebratetheartofcolorguard—synchronizeddanceinvolvingflags,rifles,andsabers—bypairingregionalcolorguardteamswithperformers,includingSt.Vincent,NellyFurtado,andAd-Rock.