When I discover an error in my usage of the language, I stop making the error. The author doesn't take this approach. The author, instead, endeavors to "prove," with pretzel-shaped logic, that there was never an error at all. Yes, language is fluid. However, during the transition period, before the mistake becomes the norm, we should recognize that we're choosing to err, rather than pretending the mistake is just hunky-dory. "Supercede" is another good example. It's just plain wrong, but, like "hone in on," will eventually become fully accepted usage.