There was an abstract of PhD thesis devoted to enhancing usability of DSeLs by helping with error messages - they had to be expressed in terms of DSeL, not Hask

There was an abstract of PhD thesis devoted to enhancing usability of DSeLs by helping with error messages - they had to be expressed in terms of DSeL, not Haskell-the-language. And linear types as a library (be it ResourceT or something other) is a DSeL. I think it is a better venue which can help many applications simultaneusly. While linear types won't.