Bill Gross is NOT crazy

Let me say flatly, Bill Gross is NOT crazy.

There was a palace coup in which disgruntled underlings gave an ultimatum to Pimco's parent company, Allianz, complaining that the "Bond King" had become difficult to work with and erratic.

Five managers said it was "us or him," and Gross reportedly quit the day before he was set to be fired.

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Some have said Gross's investment letters to shareholders were indicative of a delusional mind.

Gross is well-known for his colorful, contemplative and, often, offbeat, market commentary. But so what?

That does not make him a lunatic who deserves to be locked up, or a wild man, hell-bent on self-destruction. That is how you get your work to stand out from the pack when you're trying to make the bond market interesting to investors who might otherwise never read his missives.

Read MoreGross exit not about investing strategy: Pimco CEO

Was he a demanding boss? I suspect so.

Was he dismissive of other's ideas? Perhaps — and it wouldn't be the first time that would be true of a highly driven and successful money manager.

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Legendary hedge-fund managers from Michael Steinhardt to Julian Robertson to Stan Druckenmiller to my old boss, Steve Cohen were, or are, reputed to be impossibly difficult to work with.

I know all of them quite well.

Michael Steinhardt, who is extraordinarily gracious in social setting, would admit that, in his day, his voice would thunder so loud that the walls shook when he berated an underling. Steve Cohen, who says he has mellowed in recent years, would also acknowledge rattling a few cages in his younger years, which, I suspect, would be a mild way of describing those interactions with SAC employees.

Socially, almost all of these folks are amiable and surprisingly gentle outside the office. But like highly skilled athletes, they are animals when they get on the field.

(Not to mention that there is no shortage of inventors, CEOs, artists, actors, directors, musicians, TV personalities and even news folk, who are difficult, demanding divas, whose products we buy, paintings we purchase, movies and shows we watch and music we listen to, without caring a whit. It makes news, but we give them a pass because they are famous!)

While Bill Gross still primarily is allocated to the U.S. bond market, he warned investors at year-end that he views "the current environment with caution."
Jim Young | Reuters
While Bill Gross still primarily is allocated to the U.S. bond market, he warned investors at year-end that he views "the current environment with caution."

By the way, that is what investors pay for. They don't want someone ordinary managing their money — they want someone extraordinary.

It is altogether possible that Gross, as the years wore on, and his firm grew to its multi-trillion size, had become imperious, dismissive, or erratic. (It's possible, though I don't have any firsthand knowledge of it. It has been a few years since I have interacted with Bill.)

But no one can play this game, at this level, for this long, without snapping once in a while. He may very well have lost his investing edge.

Steve Cohen once told me that as one gets older, it becomes a little harder to see the high, inside fastball that, in your younger days, was easy to hit out of the park. (Ironically, it appears that Steve's ability to hit the long ball doesn't seem to have diminished all that much despite some recent setbacks.)

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But the assertion that Gross has lost his marbles is grossly unfair. The Bill that I have known for over 25 years, like many of his peers, is a keen observer of markets and economics. Right, or wrong, he has developed insights into the financial markets that come from years of disciplined study, intense information gathering and trading skills that are unique to only a certain breed of money manager.

Now that he has moved on to Janus, named for the ancient god of endings and beginnings, Gross may just turn out to be crazy like a fox.

I will bet the 70-year old Gross, like George Soros, Julian Robertson, and other aging legends, has not yet lost his touch for good. Soros is active. Robertson is more successful today than he was at the height of his hedge-fund days. I wouldn't count Bill out and I wouldn't call him crazy.

There is another chapter yet to be written in this story and it might be titled, "Hell Hath No Fury Like a Bond King Scorned!"

Commentary by Ron Insana, a CNBC and MSNBC contributor and the author of four books on Wall Street. He also delivers a daily podcast, "Insana Insights," and a long-form weekly version, both available on iTunes and at Follow him on Twitter @rinsana.