You guys are just confused.

To Rockman, thickness refers to the volume of food (more food = thicker market, less food = thinner market), while the the price difference between the peak and valley is the depth.

Well, Rockman is a mathematician, so if you think of it in terms of sine-waves, "amplitude" would be the depth, and "frequency" would be the thickness. :)

A thin market is easier to cause buyout.