Marissa Mayer's secret mantra: Thank you, Jerry Yang, thank you

If Marissa Mayer hasn't yet sent Jerry Yang a box of chocolates, that's a faux pas in need of immediate attention.

Yang, the unfairly-maligned co-founder, made the 2005 call for Yahoo to pay $1 billion for a 40 percent share in a little-known Chinese e-commerce company called Alibaba Group. This ranks as one of the most brilliant investment decisions ever. Last fall, Yahoo parlayed that original stake into $6.3 billion in cash and $800 million in preferred shares. And there's more in store as Yahoo still owns roughly 24 percent in Alibaba, which is expected to go public this year.

Without Yang's prescient move -- the Alibaba connection is the big reason behind the doubling in value of Yahoo's shares in the last year -- it's hard to believe that the boo birds would be on Mayer's case for buying 30 different companies in the last year while failing to reverse the deterioration in key areas. Consider the following:

• Facebook has now replaced Yahoo as the No. 2 digital ad seller in the US.
• Yahoo's U.S. digital ad revenues fell to a 5.8 percent share in 2013 from 6.8 percent in 2012
• The company's worldwide digital ad revenues dropped to an 2.87 percent share in 2013, from 3.37 percent
• Yahoo's share of search advertising revenues fell to 6.1 percent of overall US digital search ad revenues in 2013 from 6.6 percent a year earlier.

Those stats, compiled by eMarketer, offer a sharp contrast with the optimistic, happy talk in Mayer's comments during Tuesday's conference call following another drab quarter. To be fair, today's Yahoo is in a lot better shape than it was before hedge fund manager and former board member Daniel Loeb pushed to hire Mayer away from Google.

"I would say the steps they've taken to increase usage and make it easier for advertisers to do business with Yahoo are a positive," said eMarketer's vice president, Clark Frederickson. "Obviously though, those steps haven't translated into revenue growth yet."

Yahoo selected Mayer as chief executive in July 2012 and at a certain point, she gets to own the turnaround story. Or lack of one. For now, Mayer can blame ousted COO Henrique De Castro for not doing more to stem the decline in Yahoo's display advertising business. During the conference call, analysts twice tried to draw her out but she took the high road, only saying that De Castro wasn't a fit.

So for now, she's remaining true to form, counseling patience and talking about the continuing transition to mobile and adding strategic pickups or services to draw in more users.

A good example is the recently-launched Yahoo News Digest. The mobile app is updated twice a day with summaries derived from machines and human editors. It offers 7 to 10 stories with each edition, and includes text, images, and video and links to the original sources. It's beautifully designed. It might appeal to a casual news consumer looking to keep up on the big news of the day. It's nice, and one of many initiatives to prettify or enhance Yahoo, but ultimately doesn't move the needle. In the last year, Yahoo has acquired 30 companies, prettified several apps, launched new "magazines" for food and tech, bulked up on Tumblr, and made high profile hires like anchor Katie Couric. Will all of this activity add up to a Yahoo that is more than the sum of the parts? Mayer wants more time to make it happen.

Based on the current quarter results, she will need a lot of time. And thanks to Yang, she's got that luxury.