Yes, that is absolutely correct. We have done it more than once. Remember, when you are sitting in front of a judge and jury, and the lawyer is drilling you about how you made your filler metal selection.... what will your answer be?
Maybe it's because I have seen it happen, but I always do my work as if it were going to a lawsuit. It seems so many end up that way these days. It's one thing for the "owner" to engineer and direct you what to do in writing, it's another for you to show up and the owner/engineer lay the responsibility on you. You better have your paperwork spot on in case something happens. Because the owner will claim they hired you for your expertise, and a jury is not going to buy "when it doubt, 309 it out". LOL. And most likely, if you are not performing to the industry standard, your insurance company might not back you either.
Some times it's better in the long run to turn a job down. You might have to skip a meal, but save your company in the long run.