XML is a gleaming beacon of purity and grace compared to the CTCP spec[1]. Something that should be relatively simple: "allow very basic RPC using inband signals." The mess of incoherent and mutually contradictory statements about how quoting these messages should happen makes it likely that anyone writing a bot either uses an existing library or still wakes up occasionally in teh middle of the night in a cold sweat.

[1] http://www.irchelp.org/irchelp/rfc/ctcpspec.html