I'd like to recommend that the people at the workshop take a look at the exercises Tohei does in the video:
They're good exercises.... and how/why to do them should be fairly clear now.
Looks like the standard Aiki taiso from the Ki Society, at least the ones I remember from my training during the early days of the Ki Society. I am not sure if current Ki Society dojos here in the states still do them all, but I have noticed some of the exercises are performed in the AAA, AWA, Iwama & ASU dojos I have been at recently.
Learning the movements are easy, however, the hard part is doing them while applying Tohei's four principles of mind and body coordination - extend ki, keep one point, keep weight underside, & relax totally - which, of course, is the purpose of the exercises.