Doing the math: 1.60mm x .03937(inch/mm) = 0.062992(inch, value of 1 thread.) .062992 inch x 16 (tpi) = 1.007872 inch.
They are the same for almost any practical purpose, but not exactly the same. So I guess the question remains as to what the actual spec is. Would it matter? These threads debate this sort of thing all the time. IMHO probably not.
