I asked Steven Drake the same thing in case he knew someone that knew "why" - he just posted about this piece talking about the "gold flakes" (ie the allied down product). What's confusing is Allied does have a hyperDry fill, but ExpeDry (
https://alliedfeather.com/info-room/products-innovations/expedry) is the Allied product used in the HyperDown sleeping bag.....but not the HyperDown Jacket. He's probably got a test piece that does have that fill, but why not send it to market with that (cost likely)?
"a technology called FUZE to create tiny gold particles that permanently bond to the down inside the insulation chamber, creating an electrostatic barrier that stops, say, humidity from condensing into water."
I know that doesn't actually answer the quetsion, but I thought it was funny one of their main sponsored folks was talking about the jacket and having a different fill than is actually advertised.