If it is "basically...publishing business logic as a library" then why incur the expense of using such a scheme? Just publish the darn library and put it on a read-only shared directory. Why give up the use of purpose built version control and programming tools? Why give up the modularity and increased productivity that a high level language can give you?

Most of the time, it's because the organization thinks in terms of SQL and relational tables. There are better ways to do business logic.

As a language, it's pretty painful to use and you run into those limitations pretty quickly. You also put more processing in the database, which isn't great for scalability. It is nice being able to test changes via the sql prompt though. A library + console app might be a good compromise.