I'm in favor of another get-together but back to the topic.
Drilling down to the essentials: training is a method to get to the crux of the matter. What is required is proficiency, knowledge, and judgment. A person having those attributes should be willing to demonstrate that he/she has them. (I am not posting a challenge).
Is a training course required? Not necessarily but in IMHO it is the normal route to acquiring knowledge but self-study is an alternative. Proficiency: range time and drills. Judgment: experience.
At the risk of stirring the pot: an old Arabian proverb containing 'knows not' comes to mind.