In my opinion, I think that Thick and Quick is more of a solid feeling yarn, whereas a "chunky' variety would be more lofty. If you press the yarn between your fingers, even if the diameter of the yarn is similar, is one more cord-like in texture and one more squishable and you can flatten it with your fingers. The chunkiness or "loft" giving it a quick knit-ability without the weight of a heavy fibered yarn. Does that make any sense? I notice too that some "chunky" yarns will get really thin if you pull on the strand, indicating a little stretch, where thick and quick doesn't get too skinny when you pull on it. Sooo, thick and quick may make a really big or "chunky' hat, whereas a truly chunky yarn has more of a soft insulating knit quality.
I am totally rambling at this point, but I would stay in the same family of chunkyness as thick and quick may measure up as a super bulky guage.