Thus any associated supporting element cannot be arbitrary in a stipulation to place the constructions into these various categories. Suppose, for instance, that the descriptive power of the base component does not readily tolerate the traditional practice of grammarians. Nevertheless, this selectionally introduced contextual feature is not subject to an important distinction in language use. Notice, incidentally, that the speaker-hearer's linguistic intuition appears to correlate rather closely with the strong generative capacity of the theory. Comparing these examples with their parasitic gap counterparts in (96) and (97), we see that this analysis of a formative as a pair of sets of features raises serious doubts about a parasitic gap construction.
see also: WikiPedia -- Chomskybot