This reminds me of when, back in the Pleistocene, & was in Airframe & powerplant training, and was in the welding class, & was having a few questions about releasing aircraft after welding repairs,then required under 14 CFR 65, and about the skill level required to maintain airworthiness. The instructor asked what would you do, if you had an aircraft "down" on the tundra of Siberia, or the Amazon basin, or some-such, and you had to make a repair, and you lacked those skills. How would you handle such a situation, as a certificated Airframe & Powerplant mechanic?? I asked, is there a welding 'rig' on site, there in Siberia? "NO" my instructor replied. I made the comment, that if they had to bring in a welding rig, they might as well bring in a certified aircraft welder. As it turns out, you no longer have to demonstrate welding skills as a "certified Airframe & powerplant " mechanic, but you do need to recognize a bad weld, and have the rudimentary NDT skills to verify your observations.