What is the throttling rate that GTalk applies to XMPP messages?

Question

Even after throttling down to one message per second, after about 20 messages GTalk starts bouncing XMPP messages with ...

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What is the maximum send rate for XMPP messages through Google Talk?

Answer 1

Empirically a delay of a few seconds when sending after about 10 messages appears to allow continuous sending but I'd still like to know a more accurate answer. Closing for now unless someone knows better.