Those Have to Be About as Common as Unicorns

Reading this article in the Telegraph regarding a recently found photo of Florence Nightingale, one turn of phrase struck me as funny

Mark Bostridge, the author of a forthcoming biography of the great reformer, said: "She was extremely reluctant to be photographed, being determined 'in no way to forward the making of a show' of herself, partly for religious reasons [she was a strict Unitarian] and because she regarded any personal publicity as detrimental to the causes of public health for which she worked so tirelessly."

"strict Unitarian"?

There's such a thing?

I always figured Unitarianism was the last stop before full on agnosticism or atheism. I've never met a Unitarian that could be described as 'strict' in any way shape or form (other than a strictly, raving, liberal).

Maybe it's just my experience in Santa Monica talking.