I have a theory

A major reason Reformed culture tends to schismatism is because our most powerful stories are the legends of those who heroically stood up for 'the truth', being prepared to fight and split over ideas. Athanasius, Luther, Machen, et al.

It is ironic, I think, that a tradition in which abstract concepts have triumphed as 'the truth' nonetheless continues to reveal what really counts: narrative and the power of story. There's a lesson in that.