My favorite gross misspellings are on job applications. At the last shop at which I worked, there was a welder who couldn't read. He knew it, I knew it, everyone else knew it, but it was never mentioned. He may not have been able to read, but he was an amazing welder. I think a good foreman is able to use the resources at his disposal to make chicken soup out of chicken <insert base vernacular for feces>.
My favorite one was getting a call that my erection drawings had some "mistakes" only to go out in the field and find out the iron workers had shortened some braces "to make them work".