What is the advantage of this "mirrorless" K01 over a regular size DSLR?

I don't really get it. Let's not consider the design of the K01 for now (I am sure there are people that are dying for a yellow plastic camera).

• They use the same lens.

• They are about the same size.

• They weight about the same.

But look at the disadvantage:

• no phase detection AF

• no viewfinder

• smaller grip (maybe less comfortable)

Other manufacturers offer the "Advance amateur" model, which often shares the same high end sensor (and other backend stuff) but with advance functionality/control removed. For example, Canon 7D -> 60D -> T3i, Nikon D7000 -> D5100, Sony A77 -> A65. So I think Pentax is trying to kill 2 birds with one stone with the K01 - an "advance amateur" model that happens to be also "mirrorless". Unfortunately I think that approach put this into the middle of the nowhere - too crippled for a DSLR size camera, and too big for a mirrorless camera.