Teaching Pron: Where to start?

Start with the chart. Lesson One. From the beginning. That is Adrian Underhill’s answer, for very good reasons.

1. There is no syllabus for sounds. You need every sound from the beginning.
2. ‘To do nothing is to teach mother tongue pronunciation’. Everything we do in class – listening, reading, writing, speaking involves pronunciation and if we’re not teaching the sounds of English, the student is learning with the sounds of their L1 and every repetition fixes that pronunciation.
3. You start with the body. The chart is just a guide to what the body does to produce the sound. The symbols themselves are not overtly taught, they are learned almost incidentally.

I appreciate this reasoning, it makes complete sense. Start with the chart. It works for any level, in any context. I wonder though about student expectations. Would my business English students understand the value of spending an hour or so exploring lip, tongue and jaw positions? What about an essay writing class?