Krashen

Krashen, S. 1998. Teaching grammar: Why bother? California English 3(3):8.

(Audience: high school/secondary school English teachers in English-speaking countries)

Studies show that grammar study has no impact on writing growth or language development in general, and research also strongly suggests that writing quality is the result of reading. There are, however, reasons for including some grammar study in English classes for native speakers at the high school level. (1) language appreciation, or linguistics; (2) as an aid to editing: Even well-read people may have gaps, places in which their version of English is slightly different from the accepted standard.

Available at: http://sdkrashen.com/articles.php?cat=3 or from http://sdkrashen.com/content/articles/teaching_grammar_why_bother.pdf