When I was growing up in Northeast Texas, I always thought the term was synonymous with "hillbilly". I didn't know it was super bad for cajuns until the Saban stuff.
I am born and raised in Louisiana (I got to Texas as quick as I could) and I have NEVER known coonass to be a slur. Maybe I was naive, but everyone in my town used it as a joking way of calling someone "crazy". Many cajun are proud to call themselves coonass. I may be completely wrong, and if so then I apologize to anyone I ever offended, but I never understood why Saban got into so much trouble for that remark.
I don't use it often, but when I do, it's most likely to be in the context of "I'm half coonass, half yankee." Seriously, I am. My father's family is originally from Hineston; with many of them growing up in/around Lake Charles. I've heard the term all of my life used by my family, friends, and neighbors and never in a negative way.
I dunno, fly ... I have heard the word a few times since moving to Texas and was curious as to how such a bad sounding word could be so socially acceptable.
My thinking is that anytime ass is used as a suffix -- or prefix for that matter -- and applied to an individual or their heritage or ethnicity it could be considered at least pejorative.
I grew up on the tx/la border. Use to and still do hear it all the time. Especially from full blown cajuns themselves. Until the Saben thing I have never heard of anything negative associated with the word "coonass".