You will find that there are variations, often due to the first language of the particular group [Thai, Sinhalese, Burmese, etc...]. That document is, obviously, based on Thai conventions. I'm most familiar with Thai-derived chanting, and even then there are some variations. It's quite noticeable to me that the Western Ajahn Chah groups chant with a slightly different rhythmic sense from the Thai monks I am more familiar with [the AC groups sound more measured and less "bouncy"]. The key think with chanting is that it's a collaborative effort, so one needs to adapt to the local situation.