Nope, that's a legitimate error that I made. I'm not defending the letter; it's terrible. But I do think we should limit criticism to actual mistakes (however nitpicky) rather than personal style preference. Nobody likes losing points on a paper just because the professor subjectively dislikes it.
Hrmm, in this case, the professor has a moral obligation to “subjectively” demoralize the “student.”
You know what? That's valid.
"But I do think we should limit criticism to actual mistakes (however nitpicky) rather than personal style preference." So, should I sue my English teachers from 7 - 12 grade saying they were grading based on THEIR personal style preference?
High school English teachers can be the worst. Context matters too. I would criticize the overall tone of this letter as unprofessional and inappropriate for government correspondence, but the sentences identified as "run-on" by the proofreader aren't abnormally long for legal writing.