A self-described “appellate lawyer and persnickety dude,” he’s delightfully witty and scathing* in his tweets – a college-level course in grammar.
Follow and learn!
*Normally I wouldn’t use “scathing” to describe something positive. However, in the case of proper grammar, spelling, and punctuation, scathing is appropriate. There are too many means of checking your writing to ever claim ignorance.