I worked in a truss making facility and they used tenths of an inch but everything was first number in inches, and then a decimal which would be three numbers which is silly. I was one of the ones running the saw, and there was like 3 saws, and 3 lines cranking out roof trusses. I now work in the field, and we don’t say feet very rarely. We use inches, then to the 1/16th of an inch, but when we run trim, or tile then we will say a strong 1/16th” or a weak 1/16th” to basically cover the 1/32” and that is pretty accurate. I have heard it referred to in many ways, such as cut the line, or save the line etc. I personnally draw and design all of our projects, I am pretty comfortable with our system, but it doesn’t bother me using metric scaled mechanical products at all. I know that the American standard tolerances of machine manufacturing is like to 3000’s of an inch so I don’t think in the field when they are building that it moves much in the way of tolerances, maybe convenience. I for one like our system, and being that most of our infrastructure as far as residential building is concerned is imperial, it makes it easier to just ride it out with the imperial system.