The templates directory (/opt/dell/crowbar_framework/templates) is created and populated by barclamp_install.rb. It was introduced in already quite some time ago (August 2012). By this commit:
https://github.com/crowbar/crowbar/commit/0940793e498311f236d68fb1da75e5918aecda0a

I'd suggest we just use that "templates" directory until the move to crowbar.yml is completed. BTW, what's the reason for that move? Won't that inflate the already large crowbar.yml files even more?