I’m thinking variations on the E core will implement a type of plastic cage in future designs. I liken it to the use of high tech plastics in auto construction in general. No real reason that cage has to be made of metal. Witness plastic valve covers, plastic manofilds, plastic pressurized radiator overflow bottles (maybe a bad example), plastic radiator end caps. A little plastic cage is a no brainer. Might as well accept it because it is coming.