The only way this code would affect an affiliate is if they had managed to get a party poker URL, with there affiliate code into the search results.
even someone who ranked for “party poker” for clone site such as “playatpartypoker.com”, would have the traffic from the SE come to playatpartypoker.com.
so when the player lands at party poker the referrer is “playatpartypoker.com” not the SE.
i think that’s the point that Croup is making?