I couldn't of said it better myself.

The publications manager asked me if I'd seen William Safire's column this weekend on of. I immediately said, "You mean like when people use it as a verb?" Well, it's that and more.

Safire mentions a few common mistakes, and I confess that I'm guilty of at least one myself: dropping the of in a phrase such as a couple of typos. (Although I will claim I do this only in my informal writing, emails, tweets, etc., I fear that may not be the case...)

But as I've mentioned previously, the frightfully prevalent mistake that troubles me deeply is the use of of as a replacement for have. As in: I could of/should of/would of had this checked for errors.

It's disappointing to me that native speakers of English seemingly have no understanding of contractions. Surely they know that the little apostrophe means that some part of a word is being omitted, and that there is, therefore, a real and meaningful word involved here and not just some arbitrary utterance. While yes, the contracted 've in could've may sound similar to the word of, it simply makes no sense when it's written down. (Yes, this is also a root cause of apostrophe misuse, but that's another topic altogether.)

To quote Mr. Safire:

Here’s my point and proposition: I won’t complain about those confusing contractions in speaking if you refrain from these infractions in writing. Blur and slur to your tongue’s content, but when your fingers hit the keys, keep faith with clarity.

Hear, hear!

P.S. Since I already got one email about this: the word "column" in the first sentence of this post is the link to Safire's original piece.