All right, so maybe it's not exactly what "piping" refers to, but just saying "lines" sounds redundant. However, the endpoint is unavoidable: Costumes in the new DCU look incredibly cluttered. Speaking as an artist, adding random lines everywhere does not make a character fun to draw. I'm not necessarily asking for oversimplified, completely smooth outfits (such as exhibited in the Timmverse cartoons), but all of these just take the concept way too far--and while on one character it may be understandable (if still annoying), when just about every other costume has it, it just becomes flat out laughably ridiculous. Check out some of the worst offenders:
Armor for Superman, lack of pants for Supergirl, Deathstroke's anime sword, even Batgirl walking at all--all of these are topics for another discussion (one that doesn't belong on this blog), while all I have eyes for are the lines, lines, willy-nilly lines, as far as the eye can see.
Blue 0.5 mm needle tip pen
Serif PhotoPlus 6.0