CASI or PSIA instructor manuals

Hello again

In order to educate myself a little more about how the
professionals teach as well as hopefully correct some of
my own lazy habits that I may have got into, I am considering
buying the "AASI Snowboard Manual" and the "AASI Snowboard
Movement Analysis Handbook" from their site.

https://www.psia.org/oms/store05/home.asp?cat=EDU&sub=2

If they had a DVD instead of a VHS, I would get that instead
of the second book perhaps.

Does anybody have any comments on these for self-learning ?
Or are they useless without taking the course ?

I have actuallly read somewhere that the Canadians' CASI
literature is better but I was unable to find any of
their instructor manuals available on
http://www.casi-acms.com
Does anybody know where to get them ?
Thank you all and happy new year

Heather