I just got reminded that his porn comics existed and I started sweating on the mortal coil beneath me.
Its weird that I have to explain this, but the main reason his art looks like poop whenever he tries anything bigger then a newspaper size comic (and even then) is because he has adopted certain artistic characteristics from comics that go back as far as the 60s.
Lets take this for example. The square face with a strong chin is a symbol for being manly, a rounded face with blush marks is a symbol for the feminine etc (And yes, i'm calling the way David draws himself effeminate). The point is that this is not an attempt to represent or stylize real forms, these are vogue 2d shapes/symbols. There is minimal detail, because the panels are small and the symbol making is supposed to make the eye skim on the lack of detail.
This is fine for the newspaper size scribble he calls a webcomic (certainly nothing worth the 5k he seems to be milking), but the moment he upscales and, dear god, tries to actually make a porn comic, it becomes apparent how amateurish his art is.
The effect is the same as taking a newspaper comic with art that looks fine in a 8x4 cm panel and magnifying it to the point where every wobbly line and shape looks like spaghetti. You may as well have cardboard cutouts bumping into each other because the end result is blobs of colors and lines that are erotic in the same way poring hot wax on your crotch is warming.
If Dave or anybody else thinks this is passable art, they demonstrate at best a higher level of incomprehension.