Grammar and Grammatical Mistakes

Every theory in grammar has to explain, where ill-formed sentences with syntactic mistakes come from. Some noted scholars would like to believe that principles UG are easy-to-get, since they are a psycholinguistic reality.
My collection of syntactic errors in current Russian mass media texts, all or most of which presumable were generated by native speakers, may support a different viewpoint: syntactic mistakes are often made in a situation, where a speaker is partly conscious about grammatical constraints, but treats them in a wrong way.
zvenig2007