Agreed, but before JEE 6 web profile, essentially all before JEE 5 was much much harder to work with. Deploying a basic demo EJB 2 app on some ancient JBoss too

Agreed, but before JEE 6 web profile, essentially all before JEE 5 was much much harder to work with. Deploying a basic demo EJB 2 app on some ancient JBoss took our team of "enterprise developers" about two weeks. I'm just saying Scala is nothing exceptionally more complex than many other things that are or were used by so called "enterprise developers". BTW: on the last training in databases I led we used Scala as a language in which some sample programs were created. The group was not specifically prepared for that. Actually they were even not all Java developers. They had no problems in understanding Scala code and modifying it for the purpose of the excercises.