But given the 10% drop in Yahoo!'s stock in a few short days, this decision by Mayer to put out that 8-K is her first big mistake -- and a sign of her inexperience as a CEO. As Kara Swisher said today, one investor described now being in "Marissery."

Mayer probably thought she was sending a strong message to employees and shareholders that she's in charge now and will do what she thinks is necessary to create long-term shareholder value, including making a big acquisition.

After all, her board made the promise to return capital before she arrived and then told her she'd have full control and lots of time to turn around Yahoo! She's also taken down Yahoo!'s stock price from its internal employee intranet homepage.

Some in the media cheered this as a sign that she's all about being product-centric instead of stock price-centric.

But why did she have to release this 8-K last week? There's presumably going to be money coming in from a Yahoo! Japan stake sale. Such a deal is also rumored to be involving a cash-rich split, which means, by definition, Yahoo! will get a bunch of assets of its choosing (worth at least $1.5 billion) in addition to $3 billion in cash.

And she could also cull the bloated head count. Both of those actions would have given her ample ability to go out and do deals if she wanted to in a fairly short amount of time -- without touching the shareholders' promised money from the Alibaba deal.

Sometimes people in the Valley get a little disconnected from Wall Street. The Valley elites look down at the Wall Street elites thinking one creates real stuff and the other just makes money off it.

But, let's get real. Like it or not, shareholders are as critical a stakeholder group to Yahoo!'s future as its own employees.

I could argue that if Mayer did a better job of getting shareholders on board -- increasing the stock price by 10% instead of dropping it 10%, as it did in the last few days -- her life and all the grand plans she probably has for turning around the company would be a lot easier than it is today.

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