The theological connection between Majorism and synergism is much closer than is generally realized.
"Historical Introductions to the Symbolical Books of the Evangelical Lutheran Church"
Friedrich Bente
Perhaps the fact that at the time when Melanchthon came out boldly with his synergism, 1548, the Lutherans were engrossed with the Adiaphoristic and Majoristic controversies may help to explain, at least to some extent, why the synergistic error caused small concern, and was given but little consideration in the beginning.
"Historical Introductions to the Symbolical Books of the Evangelical Lutheran Church"
Friedrich Bente
151. Relation of Majorism and synergism.
"Historical Introductions to the Symbolical Books of the Evangelical Lutheran Church"
Friedrich Bente