Courtesy comment:
Well duh, excuse me for being totally eat up with the dumb butt.
I guess that the responsibility for who works for you must belong not to Fox but...hum....PMSNBC or CNN.
Here is a link to the home page of Luntz:
Here you will find an explanation of what it is he does. There is also a solicitation for people to join his focus group(s). This says that people who join these groups are NOT random selections done the day the event in question is focus grouped.
I am not sure of this but maybe he has different groups for Dems, Rep, and Ind.
It would then not be unusual to see the same individual at different Luntz focus group events.