With this clarification, the notion of level of grammaticalness raises serious doubts about the traditional practice of grammarians. In the discussion of resumptive pronouns following (81), this selectionally introduced contextual feature may remedy and, at the same time, eliminate irrelevant intervening contexts in selectional rules. However, this assumption is not correct, since an important property of these three types of EC suffices to account for a parasitic gap construction. A consequence of the approach just outlined is that the natural general principle that will subsume this case appears to correlate rather closely with a corpus of utterance tokens upon which conformity has been defined by the paired utterance test. Note that the fundamental error of regarding functional notions as categorial does not readily tolerate an abstract underlying order.
see also: WikiPedia -- Chomskybot