Nothing like hunting for some good will to discover the perfect Saturday Night Live sketch. Or maybe not. In SNL ‘s new promo starring this week’s guest host Matt Damon , The Odyssey star revisits his past in an effort to help cast members Jeremy Culhane and Sarah Sherman come up with the ideal SNL bit. They’re all standing at a Good Will Hunting -style chalkboard illustrated with some very complicated comedy equations. “Experts have been trying to crack this for years,” Sherman tells a curious Damon, with very serious Culhane adding, “Yeah, Farrell got close once but ultimately it drove him insane.” When Damon recognizes their chalkboard method from the nearly 30-year-old movie, neither of the young cast members know what he’s talking about. “Never seen it, dude,” says Sherman. “Grew up in a cult, never seen a movie,” says Culhane. Watch on Deadline Left alone, Damon takes to the chalkboard like a pro, but the results are not quite up to his old standards.…