Doesn't SSL/TLS use a per-session symmetric key that is exchanged using the asymmetric server keys? Is the point of this article that even that per-session private key would be logged or re-generated and therefore prone to attack if the server private key were exposed?
If an eavesdropper records all traffic between client and server, he/she will also record the encrypted session key. If the server's private key is compromised, the eavesdropper can decrypt the session key and use it to read the rest of the communication for that session.
