That has been my experience as well, one level abstracted. Back when I was a position when I last had to organize teaching employees technical domain-specific skills, the best way we found for them to learn was for them to teach others, this was accomplished by having one generation of employees train the next and then reviewing the newly trained employees.

Then for the next round of hiring, advance the employees up the education pyramid. The trainees become trainers, and the previous trainers mentor the new trainers by reviewing the newly trained employees.[1] It was one of the things I think we did we really well and that I am really proud of (even though the business went belly-up).

When training is done is this pattern, hopefully a virtuous cycle of education is established throughout your organization.

1: Note that this was at a quickly growing company, with recruits that had little to no relevant actual know-how to do what we did.