you're right Tony,
however if one does a search on sony stalk on the riocar.org site FAQ area you get this link
Hijack Config.ini options - [amoungst a few others].

Which does indicate how to enable Stalk debug mode, which dumps out all Stalk packets to the serial port.

I would however suggest that this part of the Hijack config.ini section in the FAQ should possibly have a link to the Developer section on riocar.org which explains what the debug info means/how to interpret it.