This Linguistics class was what actually … discouraged me from writing lower-case k’s with a loop. I used to do that all the time, but then I was marked off on an assignment with no explanation as to why. Eventually, we found out that the lower-case k with a loop is not a valid symbol in the IPA. So I stopped writing them like that so I wouldn’t make that mistake again.
(It still didn’t stop me from making all sorts of silly mistakes on the tests, though.)