It always surprises me when people like Pacino or De Niro talk about going for auditions - I'd imagine they had a large enough body of work that directors would know what they can do.

But then it occurs to me that they won't have seen them in -this- role acting -this- way for -this- film/play/whatnot and that's what the director needs. And given the amount of money and risk involved, it's probably wise to check first...