CMcG, The reference in the book is no more than what I wrote; there is no elaboration on the topic of the kilt or circumstances for wearing it. But I would agree with your reading of this. And I think, Bugbear, that the word 'ritual' in this context is being used with a less specified meaning. Rather than thinking of ritual as a prescribed set of actions designed to bring about a specific effect, think of it as an occasion which has been set apart from the mundane, the usual daily life. In this reference I think the author is trying to use the word 'ritual' to mean 'not normally done.'