I go on far too much about linguistic correctness in this blog. In a meta-sense, though: not about which usage is or isn’t correct, but what it means to say that someone’s usage is or isn’t correct, and when that’s even a coherent concept (see, for example, here, here, here, here, here, here, here, and here). It’s probably a bit of an obsession, and my posts about it are almost certainly too long. So here’s a one-sentence summary:
Someone’s use of language might be said to be incorrect, but without reference to what speaker was trying to achieve, this is incoherent.
I think that covers it. Maybe.