The link I posted was for his 3nd course (2013): Tranquility and Insight I think the one you mentioned is the first year’s series (2011). He probably mentioned this topic in various places in all those lectures.
Hmmm, wonder why the link didn’t work. I just tried and it did. Here is the full name: http://agamaresearch.ddbc.edu.tw/wp-content/uploads/2014/06/lectures2013.htm I think somewhere on SC there are also links to his past courses. @ Brenna has the links here.