My personal assessment would be that DC decided some years ago that they would compete in a larger market ... I think, since that decision was made, they have tried to be everything to everyone ...
This is a very, very slippery slope.
1991 350 SDL (200K and she ain't bent, yet)
former 2002 E320 4Matic Wagon - good car
former 1985 300 CD - great car
former 1981 300 TD - good car
former 1972 280 SEL - not so good car
a couple of those diesel Rabbits ...40-45 mpg