Naw, he uses Tech pens and a small brush for the flowing lines which looks really awesome IMO. I tried to do it with my comic, but using a brush pen...results varied but generally sucked so now I just use the brush for the speech bubbles.Phenomonal.
Is he drawing those with markers? Heck, even if he sketches them in pencil first... here I thought he scanned them in then used some Photoshop wizadrly for the line thicknesses - but no, he just, uh, does it.
I wonder if DCS knows that he's inspiring people to draw?