[sanddrag]

I'd say you need to be able to use your hands in order to apply your mind well. If you're designing a vehicle, but have never driven one, I don't think that is a good idea. If your designing an aluminum widget with features on 12 different faces, but have never machined anything, I don't think that is good.

I can't definitevely pick one of these options because I think neither is optimal, but I am leaning towards the side of engineer designed and student built, since I think you need to have some intuition about building things before you go designing them.

If I didn't know anything about the physical build process, I would probably design very outlandish things that would require a very large amount of resources to manufacture. Knowing how to build first allows one to put some limits on his/her design so that it can actually become a reality.