In 2008, the jazz trio Medeski-Martin-Wood toured for some time only playing new, unreleased, mostly improvised pieces. After the tour was over, they recorded all those pieces, and released a trilogy of albums called Radiolarians in 2009 (I've listened to Radiolarians III, and I like it).
I think it would be cool if DT did something like that - if they played new written/improvised music for some part of each show, and later on recorded and released it as their new album.