Two useful articles from the New York Times ’ Opinionator column: Ben Yagoda’s Fanfare for the Comma Man and its sequel The Most Comma Mistakes . The editors I assume wrote the titles and Yagoda should not be blamed for them, though I fully understand the temptation the editors faced and failed to overcome. His book The Sound on the Page: Style and Voice in Writing is quite good, as is his history of The New Yorker .
For what it’s worth, I disagree with him about comma splices. Sometimes only a comma splice gives the effect you want, as in, as it happens, his first example, where his suggested semi-colon might make more of a break or pause than the writer wants would make more of a break than I would want if I wrote the sentence, anyway. It’s the difference between touching the brake as you go past the stop sign and actually slowing to look both ways.*
Comma splice, he explains, is “a term used for the linking of two independent clauses that is, grammatical units that contain a subject and a verb and could stand alone as sentences with a comma.” The rule against them is one of those rules more formal than practical, at least when applied as a rule that should almost never be broken. The clauses may be independent but that doesn’t mean they have to be that independent. He effectively grants this point by mentioning Beckett’s splicing at the end of the article. Beckett was touching the brakes.
* Not, let me say to the police in any state in which I might happen to drive, that I’d ever do anything but come to a complete stop at a stop sign.