@JTT,
Nope. No sources that I can find which is interesting, at least to me, because I know I started using the double quotes for speech and single quotes for irony or speciality a long time ago, though not as long ago as grammar school.
The only clue I can find is that single quotes are used in linguistics to indicate a particular use of a word. I do like reading about languages, I'm reading
The Language Instinct at the present time.
I have a vague memory of discussing this years ago with one of the editors I was working with on a series of children's stories, but that's it.
I've asked you twice whether you think using the marks the way I have described leads to better clarity and you haven't answered. I expect you won't or, if you do, it will be in your inimitable caustic style.
Fire away.
Afterwards I intend to get back to the subject of this thread. You may continue to attempt to hijack it as is your wont.
Joe('love')Nation