[msbarnett]

Anyone who's worked on the PGP project would be the first to tell you that PGP does not and cannot encrypt the email's metadata (to/from, subject, timestamps, etc).

All PGP does is encrypt the inner message body. All of the metadata that TLAs love to analyze is sent in the clear (at best inside a TLS connection, although the SMTP protocol unfortunately makes it incredibly easy for well-positioned network attackers to downgrade these connections to in the clear)

[giantrobot]

While not a silver bullet, anonymous remailers can strip out a lot of metadata. Mixmaster remailers can also help against traffic analysis.

While not as popular as they once were networks of remailers are fairly easy to spin up.

[msbarnett]

None of this has anything to do with the incorrectness of the assertion that PGP would “beg to differ” that end-to-end encryption of email is impossible. Playing 3-card monty with your message is something else entirely.