Why Shouldn't a and B Be Split?

"You have one of those up your sleeve that i could take a cack atk, this isn't a really hard one," he says. "So many of the examples you have in the book have splits that seem to me much more surprising and counter intuitived." He asks: How should the air fare be divided between the group in san francisco and the group in chicago? And if we can get the two parties who are arranging these talks to cor nate, i can do a triangle route, rather than doing two round trips.