"Here's what I've learned over the years. I'd tell him some dark secrets about something, a girl or something I did. We'd be alone at night, having a beer or coffee... and I'd say, 'Listen, I did such and such, and please Bobby, you're my buddy, don't say anything. He'd say, 'Yeah, yeah, sure.' Then he'd wait until there's a room of 500 people and say, 'What about the time you f**ked that girl?' or whatever. He's done that to me a hundred times and I'm still stupid enough to tell him private s**t. He is the most blatantly honest guy." James Caan has learned not to tell all to pal Robert Duvall over the years.