Editor here. I do this for a living, and have for (literally) decades.

I have considerable patience with new meanings for old words (e.g., gay), but very little for self-inflicted grammar injuries (e.g., if I would of known). The former is evolution in the language; the latter is the bastard child of ignorance of verb forms and refusing to revise after writing by ear.

The great glory of English is its bewildering variety of vocabulary, so I shake my head in pity over a text that confuses "decimate" and "annihilate", "substitute" and "replace", "flaunt" and "flout". Today, I read in the Globe & Mail about a new law in the Province of Quebec that "bans public servants from" wearing outward and visible signs of religious belief -- irritating to me because one bans things (automatic weapons, for example) and activities (such as pissing in the gutter), not people. People are "forbidden to" do something, or "prevented from" doing it.

For the advanced class, we also have the gradual disappearance of the preposition "of" (representing the genitive or possessive case), now being overtaken by "for" (traditionally used to translate the dative case, and to indicate purpose or advantage). We used to have "centres *of* excellence", but we are now seeing "centres *for* excellence". In my youth, the oldies radio station in Ottawa would have been called "Ottawa's home *of* rock music", but lately it has become the "home for rock music". Why does that matter? Well, to me, the form using "of" indicates the actual presence of rock music, but the form using "for" indicates only the intention of providing rock music, but not necessarily the actuality. That distinction (admittedly subtle) has apparently disappeared while I was not looking.