How does Adobe define "analogous" colors?

The Kuler color wheel imposes some rule on a palate of "analogous" colors, but it is not clear what that rule is. The rule does NOT limit the  colors to three adjacent colors on a wheel of 12 basic colors.  In all definitions of "analogous color" that I have read, "analogous colors" are defined as three adjacent colors on a wheel of 12 basic colors.

So what is the Kuler color wheel doing when a user selects the "Analogous" color rule?