Amid the seasonal rock fall of weird-shaped box sets and unopenable recorded turkeys, one project stands out as indispensable in both musical and moral dimensions. In 1965, a little-known harpsichordist began recording the Bach keyboard works for a niche French label. By the time she finished ten years later, Zuzana Ruzickova and Erato had received every French record award, wresting harpsichord Bach away from deadhand American academics back to a middle-European vivacity. Ruzickova, resisting celebrity, Communism and the temptations of the music world, taught the next three generations of leading harpsichordists from her home in Prague. A survivor of four…