Well, I don't have any of the blogs, etc, that Adrianne was asking for, but since we're all discussing it, I'll wade in.
I do the CAT test with my non-coursing breed, and I'm okay with my dogs not being allowed to compete in the true coursing. It's a safety thing, and a fairness thing. The CAT test has less sharp angles, and the dogs run separately, both of which are hugely safer. (I talked to someone who knew of a Whippet that died during a coursing event when it was T-boned by another dog.) Also, in coursing competitively, the dogs are matched up by breed. Borzoi run against Borzoi, Basenjis run against Basenjis, etc. How would you do that fairly if you were allowing all breeds and mixes?
There is an all-breed coursing organization that has competitive coursing, but I'd be a little uncomfortable with it because of the safety angle. I know when I run Tess, she's going to be only interested in chasing the bag. What's my guarantee that the other dog out there is going to be the same?
I do kind of wish that there was a "higher" level of titling, in that the CAT test is pass/fail, which is great, but it would be nice if Tess' superlative performance could win her a little more than a dog that just barely scrapes by. However, that could be complex to set up, and might not meet a lot of support, so I'm okay with it how it is.
I wish that some of the other sports were open to dogs that can do the activity. A lot of non-herding breeds will herd, for instance, so I wish they could title in that if they can do the work. Most dogs won't fit down an earthdog tunnel, but if they will, and will do the work, why not let them? I was always sad that my Tully didn't get to play that game, which she would have loved. And I have a friend with a Miniature Bull Terrier who is bigger than Pirate, and does earthdog, so the "won't fit" argument doesn't hold. Some of the rules about which breeds can do a certain activity are sort of arbitrary.
Most likely, if herding, gundog events, etc, were open to all breeds, there wouldn't be many off-breeds participating anyway. But I still wish that those who wanted to, could. I will say though, that I don't find myself caring as much these days, with so many things available to all dogs.