02/25/2013 11:16 am ET Updated Apr 27, 2013

Marissa Mayer's No-Flex Policy Old School for Young Mom CEO

How disappointing.

Working moms of all stripes were excited last summer when Yahoo! named Marissa Mayer CEO, even as her maternity leave loomed just a few months away. Yes, she soon concerned us fellow working parents when she immediately committed publicly to a two-week maternity leave. But I still had hope. We all knew she had a troubled company to turn around -- maybe her plan was to lead by example with a flexible work schedule?

Alas, no. Instead, her plan as announced last week is to lead her workforce back to the last century by banning work-from-home policies across the company. Lisa Belkin called out the new policy in her recent blog The Huffington Post:

"Speed and quality are often sacrificed when we work from home," says the memo from HR director Jackie Reses, and reprinted by Kara Swisher on WSJ's AllthingsD last night. "We need to be one Yahoo!, and that starts with physically being together."

This is a tech company, right? One in which everyone is connected 24/7? Just checking. Because Yahoo!, of all companies, should be one that is primed to take advantage of all the productivity, engagement and loyalty gains study after study has found is tied to workplace flexibility. By taking away employees' ability to decide how and when they work, Yahoo! has effectively shot itself in the foot as it limps into the future. Working Mother created this simple infographic, which rounds up all Yahoo! needs to know about the impact of flex on your bottom line.

A few weeks ago, I wrote an open letter to a Mr. NoFlex boss, explaining how fear of flex hurts his business. I'll be honest: When I wrote that letter, I imagined writing to someone who hadn't changed his ways in 20 years or so and needed a little help to come into the new millennium -- an era in which 98% of employers now offer some form of flex.

Little did I know I'd have to forward that the same letter to the youngest woman ever to serve as CEO of a Fortune 500 company -- and a fellow working mom to boot. Ms. Mayer, I write you the same thing I wrote "him": You have nothing left to fear but fear itself. Give employees the power to control their workday and, I promise, you'll be pleasantly surprised.