Another week passed; and then, another. Xstrata’s interest in a nil-premium merger with Anglo American, proposed more than a month ago, is undimmed. So far it has succeeded only in galvanising Anglo into a textbook defence.

The latter has maintained a frosty silence, implicitly holding out for a premium as a precondition for talks. Anglo shareholders, meanwhile, must weigh their options. Xstrata’s proposal boils down to a plea to let its management sweat Anglo’s assets harder. A standalone Anglo requires investors’ patience.