I prefer Lynne Truss's phraseology: I am a grammar "sticker". And, like Truss - author of Eats, shoots & Leaves - I have a "zero tolerance" approach to grammar mistakes that make people look stupid. Now, Truss and I disagree on what it means to have "zero tolerance". She thinks that people who mix up basic grammar "deserve to be struck by lightning, hacked   up on the spot and buried in an unmarked grave", while I just think they deserve to be passed over for a job - even if they are otherwise qualified for the position. Everyone who applies for a position at either of my companies, iFixit or Dozuki, takes a compulsory grammar test. If job hopefuls can't distinguish between "to" and "too", their applications go into the bin. Of course, we write for a living. iFixit.com is the world's largest online repair manual  , and Dozuki helps companies write their own technical documentation, like paperless work instructions and step-by-step user manuals. So, it makes sense that we've made a strong strike against grammar errors. But grammar is relevant for all companies. Yes, language is constantly changing, but that doesn't make grammar unimportant. Good grammar is credibility, especially on the Internet. And, for better or worse, people judge you if you can't tell the difference between "their" "there" and "they're". Good grammar makes good business sense - and not just when it comes to hiring writers. Writing isn't in the official job description of most people in our office. Still, we give our grammar test to everybody, including our salespeople, our operations staff, and our programmers. Grammar signifies more than just a person's ability to remember high school English. I've found that people who make fewer mistakes on a grammar test also make fewer mistakes when they are doing something completely unrelated to writing - like stocking shelves or labeling parts. It is the same with programmers. Applicants who don't think writing is important are likely to think lots of other things also aren't important. What's the author's "zero tolerance" approach to these job seekers who mix up basic grammar?
They should be left out for a job. They have to correct their mistakes. They aren't qualified for their jobs. They must be severely punished.