> 1) both of our MTAs do STARTTLS. And gmail is only TLS. What you're implying here, i.e. that the communication is encrypted anyway, isn't how E-Mail works at

> 1) both of our MTAs do STARTTLS. And gmail is only TLS. What you're implying here, i.e. that the communication is encrypted anyway, isn't how E-Mail works at all. Even if the GMail MXs are configured to only accept E-Mails over TLS, the user's sensitive E-Mail may, depending on his settings, traverse multiple servers with less secure settings before a connection is ever initiated with the GMail MXs. If someone's E-Mail is going to be MITM'd it's far more likely to happen between the Internet café he's sitting in and his ISP's badly configured SMTP server than between his ISP's SMTP server and GMail's TLS-using MTA. GMail using TLS will do nothing to protect against the message being MITM'd, whereas GPG would, because it's end-to-end encryption, unlike TLS settings for individual MTAs in a possibly long chain of mixed or no encryption before a message reaches you.