Stylometry's a real thing. It gets harder the shorter the sample is, and it's much easier to say "this text matches X's verbal tics better than it matches Y's" than to confidently point at a specific person like this post is doing. Fishing for a similarity measure that supports your desired conclusion is a risk. Identification from style (phrases, quirks, vocab size) is a thing, though.

The program or more-raw data would be interesting.