From the comments, a quote from Sean Maxwell (who was the designer (from the markup perspective not the UI perspective) of the Case.TV web site — the person I was looking for):
I hate CAS. Whatever CAS is doing I can do better and faster. I don't mind integrating with it, but relying on it is a bad idea in my opinion.
That's clear-cut enough.
I had actually not heard any push-back regarding CAS before. I didn't know CAS sucked. And I hate stuff that sucks (RE: previous post — I Must Be the Most Demanding User in the World). So I'd like to hear more regarding the demerits, inefficiencies, and general suckiness of CAS from others. Too slow? UI sucks? Confusing redirects? Too much work to interoperate with? Other?
As a possible counter-point to this future discussion, I did write-up The Benefits of Single Sign On, which covers "handling expired passwords", "handling disabled accounts", "increased security with two-factor login controls", "interoperability with federated identity for free" (for example, the OpenID server I integrated with CAS), etc. Things I didn't cover in that 2 year old article that are upcoming features to CAS include anti-phishing measures and security monitoring tools to detect compromised accounts.
But what I want to focus on is why CAS sucks. I'd prefer it not to suck. So any feedback is appreciated so that I can attempt to make it suck less. Thanks!