Grammar Differences
A statistical comparison between the grammatical performance levels of student and professional movie reviewers.

Teaching Syntactic Risk
Teaching grammar can be useful in my opinion for helping students to enlarge their expression of ideas through a better acquaintance with syntactic possibilities, for example inversions, sentence fragments, appositive constructions, adjective and absolute constructions, the use of coordination to “plateau” ideas, etc. Our skill in bringing peripheral ideas into the context of our sentences (and vice versa in eliminating these ideas) can be improved by acquainting ourselves with the full resources of syntax available to us. Once risk is emphasized instead of rigid principles of correctness, most students can be expected to improve as writers, especially those with superior verbal skills.

Making Grammar While it Happens
My emphasis is upon a behavioral organization of words and phrases within the constraints of the short-term memory. On one hand there is ample freedom to express our ideas on a piecemeal basis as sentences expand upon themselves, but on the other hand this versatility prevents a complete taxonomic assessment of what is said during its formulation, since multiple alternatives provide the opportunity for acceptable closure. Any theory of grammar to evaluate this process will necessarily feature statistics in determining the syntactic usage of groups and individuals.