For the past twenty years, management pundits have touted the idea that informal, ad-hoc collaboration makes organizations more nimble and effective.

As a result, today's workplace is chockablock with open offices, groupware (e.g. Slack, Chatter), and plenty of emails and informal meetings.

Unfortunately, an exhaustive study from the Harvard Business Review just revealed that, far from a panacea, collaboration is actually productivity poison.

Here are some of the frightening highlights:

1. Collaboration consumes more time each year.

According to data collected over the past two decades from 300 organizations of various sizes, "the time spent by managers and employees in collaborative activities has ballooned by 50% or more."

2. Collaboration is crowding out real work.

The proportion of time spent in meetings, phone conversation and emailing "hovers around 80%, leaving employees little time for all the critical work they must complete on their own."

3. Collaboration burdens the competent.

Collaboration tends to foists work from the incompetent onto the competent, who end up doing doing the lion's share of the effort. "In most cases, 20% to 35% of value-added collaborations come from only 3% to 5% of employees."

4. Collaboration burns out top contributors.

The people who get pinged all day to collaborated and thus contribute the most to these schemes feel angry and imposed upon. As the study puts it, the "most desirable collaborators have the lowest engagement and career satisfaction scores."

5. Collaboration creates higher turnover.

Top contributors to ad-hoc collaboration "ultimately results in their either leaving their organizations (taking valuable knowledge and network resources with them) or staying and spreading their growing apathy."

6. Collaboration makes mentoring more difficult.

Ironically, ad-hoc collaboration gets in the way of real knowledge transfer. "Although 60% wanted to spend less time responding to ad hoc collaboration requests, 40% wanted to spend more time training, coaching, and mentoring."

7. Collaboration especially hurts women's careers.

Women collaborate more but get less credit for doing so. "Women were 66% more likely to assist others in need [but] a man who stayed late to help colleagues earned 14% higher ratings than a woman who did the same."

Collaboration, in other words, turns out to be just another management fad. Like all such fads, the concept sounds all wonderful and enlightened, but in the end it's just a bunch of yada-yada-yada.

Here's the real truth: people want and need hands-on managers who coordinate individual contributions to serve a common goal. This results in less ad-hoc collaboration, less frequent meetings and more real work getting done.

People also need the right to say "no" to endless requests for "help" and, above all, private offices with real doors so that they can get work done without constant interruptions.  

This isn't brain surgery.  It's just common sense.