Dealing with adversarial grant committee members in interviews

I'm applying for a grant to research topic foo using bar as my working hypothesis (and it's not really something controversial: a lot of things are easier to deal with if you assume that bar is true). Now, one of the people sitting in the grant committee has published a couple of articles arguing that bar is horribly, irredeemably wrong, and we all should assume quz instead. This person is likely to raise this issue at the interview stage.

This doesn't worry me from a purely academic perspective: there are many ways of showing that this person's arguments don't hold water, and I can literally spend the rest of the day talking about them. However, it does worry me from a "I want that grant money" perspective: if I get that question, I'm going to have just a couple of minutes to state my case and get the rest of the committee (experts in my general field, but not in this particular narrow topic) to side with me. What would be an appropriate way of framing my reply?