So GMM, you are trying to determine up front if a 53 mm Bianchi will fit someone without a stem adjustment, if I get it (finally).

I think you and Repechage (and I for that matter) are on the same page as far as setback, seat angle, effective top tube, and reach. I just recently used this strategy to transfer the well-fitting setup of my Woodrup to my other bikes that have shallower seat tubes or more-restricted saddle fore/aft travel.

Your 379 mm does not agree with my 389 mm. We were targeting the same point on the head tube.