@pleonasm - The thing is, the term "design engineer" covers quite a lot of ground. Yes, some of them are jacks of all trades and that is a wonderful thing. Often the kind of person who suits that sort of knowledge base goes on to manage projects or be a consultant or something like that.
But there are also design engineering jobs which specialize in particular aspects of design. The classic in my mind is the sound engineers who worked on the doors of a particular car, so that the sound of them closing was "just right".
I mean come on, that's pretty specific right there.