"zanderu" wrote
http://www.inbeeld.com/hull.jpg
Is this normal?

Depends on your view of "normal." (Looks sub-par to me.) Of course, it's a
little hard to say much without knowing the scale of the image. Is that an
extreme close up, a few square feet, or what?

Is this just (multiple layers) of bad paint?

Could be bad paint. If you get blisters or peels and don't feather them out
before applying a new coat, you can get an effect that looks like that.

Is this aluminium in bad shape?
How to tell without removing the paint?

http://www.fakecrap.com/products/xray_specs.html