You would hardly
find the 'double negatives' topic in that book nor would you ever be asked in class
about it.

Maybe. However, we always believe our teachers and my teachers taught me what they believed to be double-negatives, even though they were litotes.

I called you and Amused out on it and I was wrong. For that, I feel ashamed - because I can be an arrogant prick and I hate being wrong!

As for your suggestion of buying an ESL grammar book, I already did. Nothing in there about double-negs or litotes either!

The only language-related on-line degree courses that I have so far been able to find are on Literature and Humanities - neither of which floats my proverbial boat, mainly because I don't like Shakespearean 'Middle English'. As an Englishman myself, I certainly understand all the 'ye', 'thou', 'dost' etc, but it's hardly conducive to teaching ESL in the 21st century. If I am going to spend time on further study, then I prefer to study something more practical and useful. (If you know what I mean?)