Service personel should be in no doubt about the position they hold in the eye of the "Law". The "Law" is a total ass! You are expected to have total knowledge of LOAC, the Geneva Convention and all laws. It also helps if you are fighting on the winning side and are never captured by your enemy.
It is part of their job to have at least a rudimentary knowledge of LOAC, most of which is based on common sense (e.g. Don't abuse POWs).