I checked this out and in-office trained would be layers tend to fail a lot: "61 percent of the 39,313 examinees from California- and ABA-approved law schools passed the bar. In contrast, just 26 percent of the 39 law readers who took the bar exam made the grade. (Of the 10 who passed, only 2 were first-time takers.)"

It does not seem to be easy method at all.

[1] https://www.callawyer.com/Clstory.cfm?eid=916106