Parallelism is always a good thing. The specific similarity with PGP that jumped to mind is that you're not actually using your key (or recipients key) to enc

Parallelism is always a good thing. The specific similarity with PGP that jumped to mind is that you're not actually using your key (or recipients key) to encrypt the message. You're actually generating a random session key to encrypt the message contents and then you're encrypting the session key against the recipients key and sending them that. I was really taken by surprise the first time I read that, but after playing some more with crypto "obviously" you'd have to -otherwise what happens when your message is longer than your key?