I think when DuPont's patent on R-12 was due to expire, they called on their contacts in government to use the environmental activists to generate a call for a replacement refrigerant, conveniently manufactured by DuPont.
What seals the deal to me is seeing the same action for the same product by the same people.
DuPont should have stuck to providing rifle propellant for the government. Where does one think DuPont's government influence came from in the first place? I'd bet in no small part, myself...
And anyone remember when ammonia was used as a refrigerant? Get a leak in that system--nasty stuff!
Yes, largest ammonia system I ever saw was at the Coors Brewery in Golden, CO. May have been an absorber system. Don't know if they still use it.