[RL_Quine]

You can't do that easily, you still need the public key file on disk.

[StavrosK]

Not with resident key mode.

[RL_Quine]

Sort of. The keys have limited space on them (20 for some Yubikey models) for resident keys. You wouldn't want to be always using them for everything.

[StavrosK]

That's why I'm excited about SoloKeys v2, they (will) come with space for thousands of resident keys.