You answered your question above. Miles let Teo edit the albums as he saw fit so he didn't have to go back to the studio or have them record more concerts. This was clearly the case for In A Silent Way where Miles and the group didn't record enough usable music to fill an LP. So Teo just created a Da Capo repeat by copying the beginning section to the end. Apparently Teo was forced to become even more interventionist later. I assume that was by necessity rather than preference. So you are right that Miles was becoming less concerned about finishing the album himself and letting Teo take care of it.