  When Requirements Engineering(RE) models are unreasonably complex, they
cannot support efficient decision making. SHORT is a tool to simplify that
reasoning by exploiting the "key" decisions within RE models. These "keys" have
the property that once values are assigned to them, it is very fast to reason
over the remaining decisions. Using these "keys", reasoning about RE models can
be greatly SHORTened by focusing stakeholder discussion on just these key
decisions.
  This paper evaluates the SHORT tool on eight complex RE models. We find that
the number of keys are typically only 12% of all decisions. Since they are so
few in number, keys can be used to reason faster about models. For example,
using keys, we can optimize over those models (to achieve the most goals at
least cost) two to three orders of magnitude faster than standard methods.
Better yet, finding those keys is not difficult: SHORT runs in low order
polynomial time and terminates in a few minutes for the largest models.
