Target skills are simply the set of skills the designer wishes to convey using the GBS as a vehicle. GBSs are always constructed around skills and processes. Facts and cases have no place in a GBS's pedagogical goals: while they may be helpful to a student, they must not be taken as an end in and of themselves. Rather, they are taught as supporting material while the student is engaged in trying out the skills around which the GBS is built.
Target skills must be explicitly broken down to a level at which they can be taught directly, and demonstrated so that students may be held accountable for them. Processes are clearly not at this level. One cannot directly teach or assess "understanding," for example, but one can teach how to read a piece of text aloud, and assess whether a student can do it.
The Mission of a GBS
Where am I in the content of the book?