NAUI has long had CD based training that completely replaces the classroom, if desired.
SSI has a home-study option that eliminates most of the classroom time.
Both are proven and effective. Indeed, this kind of training can raise the bar rather than lower it in many cases.
In the one SSI "home study only" class I have run, there were four students; on the written there were 3 100% scores and 1 97%. Plenty of tables problems too. In the home-study course, I conduct about a 30 minute review of the required academics before each pool session rather than a formal 2.5hr lecture, so this saves some 10 - 12 hours of classroom time over the course.
On-line/CD/home study courses are ineffective, of course, with those who won't invest the time and effort required to do the work on their own, but properly done, they are as effective as classroom sessions - indeed, more effective for many.
A wise shop will offer both type courses, and a wise instructor will shift the home-study student that needs lectures to understand the material to the lecture course, and the "bored-to-tears" classroom student to the home-study course.
Rick