Just read a bit of the discussion, and at the very least I'm not sure
"surprising" is the correct adjective in terms of GTalk not supporting
encryption on s2s streams, it's known from years.
It could be "inconvenient" at the very least.
And Philippe:
Section 5.2 - RFC 6120
<< Support for STARTTLS is REQUIRED in XMPP client and server
implementations. An administrator of a given deployment MAY specify that
TLS is mandatory-to-negotiate for client-to-server communication,
server-to-server communication, or both. An initiating entity SHOULD use
TLS to secure its stream with the receiving entity before proceeding
with SASL authentication. >>
