So I read the whole Face the Nation transcript and came away with:

Dickerson asks a question (or tries to, while being interrupted by the yam, who wants to talk about something different.)

The yam either:
A. Lies his ass off or

B. Answers a different question altogether

Dickerson then

A. Asks a followup with the yam lie as a foundation—never bothering to correct the lie or

B. Moves on to another topic, letting the lie just hang there

Then, Dickerson takes one tidbit from the yam’s 90 MPH gish gallop and attempts to follow up and

A. The yam lies his ass off, with no followup from Dickerson or

B. The yam goes into a total non sequitur and Dickerson moves on to another question

All told—the whole thing was idiotic. You’re welcome.