I suspect the Class G part leaves the trainees rather "underdone" because it's one area they consistently struggle with. But then I may not be a totally unbiased observer as I'm ex-flight service.
Way back when, the flight service course was six months and covered pretty much what canadiangal mentioned. These days it doesn't need to cover a lot of the stuff that's not specifically traffic related, but I think those extras provided more rounded training - better able to cope with the weird stuff you inevitably get in G. It built a broader base.