I freely admit that I have a very carefree attitude with regard to grammar and comma usage in particular. In fact, I often place commas in the middle of my sentences for no other reason than it seemed like a good idea at the time. However, I distinctly remember that my 7th grade English teacher, Mr. C., taught me that it is not necessary to put a comma after the last item in a series before the word “and.” I do not care that including this last comma may reduce ambiguity. This is nothing you could possibly do, or say, that will convince me that comma is necessary and I will swear up and down until my dying day that it is my God-given right not to put it there. I will be including this last comma while writing lists in my thesis, but I want you to know that I am doing this under duress. I am simply sick and tired of leaving it out and you putting it in and me removing the damn thing again. However that comma will not be used in anything that I write that you do not have editing power over and when I leave this university I will never, ever use that comma ever, ever again so long as I live. So there.
Your not-so-obedient grad student,
P.S. Don’t you even think about commenting about the fact that there’s no period after the “Mrs” above because I read once that Madeleine L’Engle originally intended there not be a period after the “Mrs” in Mrs Whatsit, Mrs Who and Mrs Which (note ommission of comma–take that!) to distinguish them from the other characters in the book but the publisher added the periods because they didn’t realize she was intentionally leaving them out.
P.P.S. I totally concede the point about my mixxing up when to use “that” and “which.”