I've been doing a lot of writing lately, and I've also learned that many folks simply are not familiar with The Elements of Style by Strunk and White. Everyone seems to own a copy of The Elements of Java Style or The Elements of UML Style but are somehow blissfully unaware of the origins of these books.
If you write, you need a copy of Strunk and White sitting right next to your Websters Collegiate Dictionary.
The fact is, the vast majority of so-called book doctors are garbage. An exception would be Strunk and White's classic Elements of Style. It was originally written during WWI by William Strunk who was then a professor at Cornell, and it has since been updated by E.B.White, one of his former pupils. Strunk's strategy was to edit down the complexities of English grammar into those few basic elements which would help people to improve their writing skills. His central rule is simple: