Hedge fund legend George Soros may have made a mistake in putting $500 million into an account at Janus Capital Group that follows Bill Gross' Janus Global Unconstrained Bond Fund, says Phillip Shrotman, president of Principal Planning Service.

"When a financial genius invests in you, that's usually a good sign," he writes in an article for Advice IQ. But since Gross left Pimco in September, his old fund, Pimco Total Return, has outperformed his new one, Shrotman says.

Over the past three months, Pimco Total Return has generated a total return of 2.9 percent, compared with a negative 0.69 percent for Janus Global.

"Has Gross, whose long-term record is extraordinary, lost his touch? Soros might have made a bad bet here," Shrotman writes.

So what is Soros thinking?

"Likely, the Soros move hinges a little on the bond king's reputation," Shrotman says. Pimco Total Return returned 6.7 percent annually over the past 15 years, all under Gross' management until last September.

That beats the Barclays U.S. Aggregate bond index by 82 basis points, a huge amount when compounded over 15 years.

Meanwhile, Gross tells Yahoo that the prospect of an interest-rate increase by the Federal Reserve doesn't make all bonds toxic. "In the short term, bond investors are safe for six to 12 months, but not for 10 to 30 years," he cautions.

The 10-year Treasury yield dropped to a 20-month low of 1.64 percent Friday and stood at 1.8 percent Wednesday.

Gross says he himself suffered losses from 1979 to 1981 when the 10-year Treasury yield soared above 15 percent. "Be careful when you're making a longer term commitment and interest rates are so low."

As for the Fed, it's likely to begin raising interest rates in June or July, "but a small increase and probably one only for the year would be my guestimate," Gross notes.

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