If you're referring specifically to section 16.2.2. Using stored procedures for querying, that looks interesting.
Since we're using JPA and not Hibernate 3 (Hibernate as the persistence provider), and as I understand, JPA is a subset of Hibernate API's, I'm not sure if this would even be an option for us.
But hypothetically if it is, will it only work with one return class, in this case Employment? What if the sproc resultset returns columns from a join (n tables)? I can see this being possible, but not if the resultset is a dynamic list of columns...
It looks like this technique will call setter methods on the Employment, and thereafter you can reference/use the Employment class rather than the resultset.