> My encryption subkey was explicitly _not_ generated inside the Yubikey. I figured that was the reason. I use an offline master key and have separate [S,E,A]

> My encryption subkey was explicitly _not_ generated inside the Yubikey. I figured that was the reason. I use an offline master key and have separate [S,E,A] subkeys on my YubiKeys as well, although I generated them on a machine that is fairly well hardened and offline anyways -- mostly because I didn't want to risk losing them but also because I have multiple YubiKeys that I wanted to use them on.