Suppose early jurists held two established positions on a question, and a later jurist proposes a third. It is insufficient to argue that any third position is permissible merely because there was earlier disagreement.
For composite consensus, one asks whether the two prior positions shared a common legal conclusion or exclusion that the new position would breach. The fact that there were two views does not by itself prove such a shared conclusion.
A sound analysis identifies the exact earlier claims, their common implication, and whether the later proposal truly violates that common implication.