They're not producing sis, they're only crediting as composers, not producers.
Them being credited as composers doesn't include the fact that they might have produced it too.
William was already confirmed as a producer for example and I doubt Gaga called David just to write lyrics...
for the ARTPOP bal lshe should do a PF/BR/Judas medley an Paparazzi/Telephone medley and performed Born This Way, You And I acoustic and perform TEOG and Just Dance normally
