Happy National Grammar Day!
It should surprise no one that I am a big fan of this holiday. I am an unabashed grammar fanatic, and I will confess that seeing grammatical errors (with the exception, perhaps, of the most obscure) in professional documents, from announcements to job descriptions to newsletters, tends to lower my opinion of the company or individual. I try to resist it - I know that it's not as important to some! - but I can't help it.
I realize that English is a living language, and that grammar use will drift as the language does and eventually become "correct." On the other hand, the language is much more codified than it ever was in the pre-modern era, so to what extent is drift natural and acceptable, and to what extent is the application of new terms / grammar conventions an ad populum fallacy - that is, the idea that it's right because most people believe it to be true? I don't know that there's a singular answer. That said, I can tell y'all definitively that "ain't" ain't in my dictionary. (Y'all is probably a good example of all this! People will insist that it should be "ya'll" or that it's "y'all" if singular or "ya'll" if plural or ... this is not a debate I'm up on. ;-))
(This makes me think about the response to the "rule" about not ending a sentence with a preposition: "This is the kind of nonsense up with which I will not put.")
(Yes, I have a parantheses addiction.)
To me, though, it's more than just a debate, and there are both practical and artistic reasons for it. On the practical level, grammar and punctuation are vital for clarity. The argument for putting a comma on the word before a person is addressed is easily illustrated with the difference between, "Let's eat, Grandma!" and "Let's eat grandma." As for applying it in other situations, I think it's much easier to use it consistently than to have to stop and consider clarity every time ... especially when the definition of clarity may vary from person to person.
On the artistic side, grammar and punctuation inform the music of the written word. They ask for pauses; they group phrases together like a singer following breath marks. There is a marked difference between two independent phrases separated by a period versus the same two phrases separated by a semi-colon. I confess I'm heartily addicted to ellipses and dashes, and I constantly have to edit back my use of them, but that break, that beat, is as much a part of my writer's lexicon as any word.
Some online publishing houses have moved to a trend of removing any punctuation that is not strictly necessary for clarity. This drives me batty. To me, it's taking some of the music out of the language. Please save the commas! Catch them and release them back into the wilds of prose, where they belong.