Yes, good point about bridge position for mandolin.What’s the best approach? Simply doubling the nut to 12 fret distance isn’t good enough to get the best intonation, especially with compensated ‘zig-zag’ bridges. Using a digital tuner helps on one string but then pushes the next one out the other way. It’s less of a problem on banjos because the bridges tend to be straight and the width of the fretwire is less compared to the overall scale length.