To break down an argument in an email line by line (sometimes word by word) and answering each point separately and painstakingly, even going so far as to call grammar and spelling into question. Also, having no sense of humor. Origins- Baltimore, MD- specifically with a certain fan of the G. Gordon Liddy Show.
Oh man, Chris just went all Liddy all over that email. He answered everything like a 4th grader does and even highlighted a typo!