I looked a bit further up the help for port:
Quote:You can define 2 or 3 terminal port. if you define 2-terminal port it operates like was described above. In case of 3-terminal port it also includes internal ideal chock inductor and ideal blocking capacitor. They are work like switches to terminate or connect appropriate branch dependent on type of analysis
You're right about the fact that it should be "choke" inductor - there is a PCR (923338) for this typo to be corrected (and for the grammar errors to be corrected too!). They are only included if you use a 3 terminal port. This was added for compatibility with other SPICE simulators (which have a .net or vport component, or something like that...)
Regards,
Andrew.