On one hand, I'd be willing to go on a date with someone i'd never seen. Either there's physical chemistry or there isn't, at that point.
However in this case, the matchmakers stupid idea that somehow this will make me consider someone i don't find attractive makes me think they probably have bad ideas in general, so i don't trust who they're choosing.
Yes. Just because your friend obviously doesn't think this person is attractive, doesn't mean you will not find them attractive. Everybody has different tastes to their friends... I know I do... I would also wonder if your friend thinks you are shallow to only judge someone on their looks... So yes to the date, what have you got to loose.