Expert? Who told that lie? [8D]

Actually AMO (or whatever it's called now) states that the AMO string length is 3" shorter than the bow length, longbow or recurve. However, that doesn't always hold true--depends on whether the bow was made to AMO specs or not. I'd try to borrow a string to check and get close, or if you order one I'd go with a flemish string 56.5" long--you can adjust it 1/2" or more either way easily.

Chad