Here's a good post by Matthew Salzwedel at Lawyerist.com: "Beware of False Writing Snoots," which begins with a quote from David Foster Wallace--
A SNOOT can be defined as somebody who knows what dysphemism means and doesn’t mind letting you know it. . . . [But the] very most pathetic and dangerous sort of SNOOT [is] the SNOOT Who Is Wrong.”
Salzwedel goes on to complain about mistakes in an article written by a self-described grammar expert.
Biggest mistakes: neglecting phrasal adjectives and recommending the much-derided book, Eats, Shoots & Leaves: The Zero Tolerance Approach to Punctuation.
I recommend the post, but only after you've read my own paean to phrasal adjectives, "An Easy Tip to Make Your Writing Look More Professional." While you're at it, check out another post from the archives, "A Plethora of Legal Writing Tips."