a bunch of us in a 2-week intensive workshop back when.
It's a biological and hence biochemical process, even just 15-20 minutes a day is HEALTHY. It can be anything, some athletic coaches use a form of it to get athletes "in the zone".
I would always definitely introduce it within its cultural context and tell people about the traditional chants - especially the translations, so it isn't just abracadabra stuff, but they should understand the underlying BIOLOGICAL mechanisms, so they can use them the way each INDIVIDUAL wants to, which as I said, can be religious, or even just simple counting. The idea of a chant or mantra of somekind, either audible or silent, is to get your brain to ease up on you by holding it in a certain thought pattern that is simple and pleasant. Some people add personal visualization, others don't.
People who have kind of like brain-cyclones know how useful this is, when you're obsessing or if you're overwhelmed with worry or sadness. Meditation and yoga calm everything down.
http://www.3ho.org/