Mechanical Engineer make things work properly.
Industrial Designers make things look cool.
Wouldn't it be a smart idea if you could cut down on having to get the two people to meet and argue stuff out by getting someone who is trained in both professions?
That seems to be what PDE is all about. Training someone up to get a thorough knowledge in maths and physics and materials science and even a bit of management, too. And then make sure they can be creative too, work in teams on projects with pretty open briefs.
I'm currently studying PDE at Glasgow Uni, who run the course in conjunction with Glasgow School of Art.
In 1st and 2nd year, we spend a day per week at the Art School, doing various projects there - and the straight mechanical engineering course for the rest of the week.
3rd year is spent mostly in the studio, and 4th year can be spent here on a final project too - or that can be delayed till 5th year, and the 4th year is spent abroad or with industry.
The 4 year degree is a BEng (Hons), and the 5 year course is MEng. Both are accredited by the Institution of Mechanical Engineers (so you can go on to be a CEng, eventually)
PDE has created a new breed of young engineers whose strength lies in the capacity for creative synthesis and whose primary task is the design and engineering of capital and consumer products.
http://www.gsa.ac.uk/design/product/pde/