Fowler's dictum holds for many other prescriptive rules of grammar. In many cases, ignorance is bliss. Your writing will probably be better, because you're not twisting yourself into knots trying to avoid some illusory error, and you won't waste your time thinking about other people's grammar when you should be attending to their meaning.
There is the illusion that we speak the same language, but we really don't.
I've tried looking this up in every grammar guide I can find, but I haven't found the answer. Consider these two sentences: I bought a car to drive myself to work. I bought an alarm clock to wake me in the morning.
For my birthday, I received Don Ringe's From Proto-Indo-European to Proto-Germanic and I've been reading it while taking the train in to work.
I find that even though I'm not in academia any more it's refreshing to spend some time perusing hard-core historical linguistic geekery, particularly since I've never really delved into PIE with the depth that I should have. I suspect that many Anglo-Saxonists tend to skimp on their study of the linguistic pre-history of English, especially the earliest stages.