Quarterly earnings conference calls are usually perfunctory affairs: management's obligatory recitation of the numbers followed by preponderantly softball questions from analysts vainly seeking "color" or "granularity" on one matter or another or guidance on what numbers they should plug into their models. But Cliffs Natural Resources CEO Lourenco Goncalves breached the time-honored social etiquette of the calls in his debut performance Thursday when addressing a question from Wells Fargo analyst Stan Dubinsky.