Budo Reigi in THSYR
by Takamura Yukiyoshi is by far the best exposition of this topic I have read. Maybe there is something out of sado or shodo, but those aren't really my purview.
Funny story/Cautionary tale: In a Japanese language class one day our teacher had us sit in seiza with him so we could get an "idea" of a formal visit to someone's home. He sort of judged who was suffering the most asked them a question about summer vacation and then gave them the magic words "Oraku ni nasatte kudasai." The thing is, a couple of my classmates refused. It was funny because it vexed him a bit and I'm sure that whatever else they did they got a failing grade for that day. But more seriously, none of those classmates lasted through the term and these were not beginning students; each had invested at least 2+ years of study already.
I think you will notice if you look that the quality of the reigi before a performance or enbu of any kind is indicative of the quality of the rest.
You can predict the outcome of kendo matches on it too. The guy with the better reigi generally wins.