Part of the genius of Mr. Iyengar's legacy, as I see it, is this notion that the poses can, and must, be tailored to the students present in the class. There is no strict curriculum or set of lesson plans that must be followed; no, we are taught to teach who is right there in the room before us. Most poses can be scaled up or down depending on the students' abilities; thus, the brilliance of the use of props when necesary.
I'm glad that came through yesterday! :0)