Researcher in authorship analysis here. Yes, punctuation specific patterns have been used in the literature for this purpose, quite a bit. Removing the words also reduces the impact of the content of an article on your results (i.e. accidentally guessing the author because the topic is baseball and you only have one writer who writes about baseball in your dataset).

Typically, this type of feature is generalised of "character n-grams", but there are lots of variants.