I really like the idea of making something sloppy on purpose. I think about doing that myself because usually, the projects I do are really perfect. Sloppy is hard for me. But I have a feeling if I tried to make something sloppy it would look, planned out sloppy.
Abject=extremely bad, unpleasant, and degrading.
Prodigious=remarkably or impressively great in extent, size, or degree.
"The lack of evident skill somehow implies the presence of concept." - this may be true sometimes, but I really don't think that is the case always. I know that when I see something well made, I do think about the smarts that it takes to build it. I know that doesn't touch on the conceptual aspect of it... A piece of art that is well made would probably have to be in a museum/gallery type setting for there the be a conceptual aspect expected.
Celerity=swiftness of movement.