i think he looks like a nice weight, i cant say i KNOW dobes (and the few i grew up around, were yugoslavian so a slightly different "feel" lol) but he looks lovely.
Looks grand to me!!!! Hard to keep weight on a young healthy active dog. VIctor is just now holding steady through the winter. I found that coats and sweaters helped in past winters so he didn't burn it up trying to keep warm.