 After two of the Gilmour / Waters @-@ produced sessions , they remade one track from the Soft Machine overdubs and recorded three tracks . These sessions came to a minor halt when Gilmour and Waters were mixing Pink Floyd 's newly recorded album , Ummagumma , to Barrett 's dismay . However , through the end of July , they managed to record three more tracks . The problem with the recording was that the songs were recorded as Barrett played them " live " in studio . On the released versions a number of them have false starts and commentaries from Barrett . Despite the track being closer to complete and better produced , Gilmour and Waters left the Jones @-@ produced track " Opel " off Madcap . 
