Wildstein's version of Taking the Fifth is Laborious
Rather than stating up front that he was not answering questions, he took the Fifth on a series of questions.
It is tiresome, but since he is not the defendant in a criminal trial his appearance is not categorically 'testifying against himself.'
That said, the person asking the questions should cut to the chase and ask him what year he started working for the state, or what town he lives in... just to ascertain that he will not answer anything.
In any event, I support the 5th Amendment, and there is potential criminality here, so I am not complaining.
However... Christie heroically firing people is largely because a state employee cannot plausibly take the Fifth in an oversight hearing.
Firing people does not advance getting to the bottom of things.