Did anybody notice that I (so far) have three different answers to my question about when a model plane is "level". I tend to follow the Hossfly method of "That Looks About Right" and I suspect I'm not alone. I respect the fact that I received information from multiple sources, but it's obvious that advice from others requires some mental capacity for sorting out the best advice and applying it to your project/problem/question. Relying on "expert" advice requires that the source truly is an expert and you are capable of determining the source's credentials. If those criteria are not met, then you're at risk using the advice.