Just before the selloff in German government bonds, the manager of the Janus Global Unconstrained Bond Fund said the debt was the “short of a lifetime.” Yet instead of betting all-out against German bunds, Gross wagered they would trade in a narrow range for the time being, fund holdings postedon the website of Denver-based Janus Capital Group Inc. show.

The trade may have hurt Gross when bunds slumped more than he hadanticipated. Janus Global Unconstrained has fallen 2.6 percent since Grossadvised shorting the 10-year German bund on April 21. The losses erased thefund’s earlier gains, leaving it down 0.04 percent for the year.

“When you sell volatility, you are basically selling insurance,” Gross said inan April interview. And “when you sell volatility and you get volatility, then it’s not a good thing.” […]