Over the years, I’ve observed business leaders struggle with the fundamental dilemma of retaining current leadership with whom they have enjoyed productive relationships, or building a “dream team” of fresh talent, with perfect skills and experience as well as new ideas and enthusiasm. Here’s my news flash: Pick those you’re familiar with.

While business leaders intuitively understand that “team familiarity” (the experience that team members have working with one another) can affect how a team performs, now there is new empirical evidence developed from years of research that quantifies its benefits.

Before discussing research findings, however, let me tell you about a high-performing team near and dear to my heart that exemplifies team familiarity as a tool: the University of Minnesota Golden Gopher football team led by coach Jerry Kill.

Coach Kill was hired in December 2010, following successful turnarounds and conference championships for both the Southern Illinois and Northern Illinois football programs he led. Under that leadership, the Gophers are experiencing a successful turnaround, finishing 2013 with an 8-5 record, after a 6-7 season in 2012 and a 3-9 season in 2011. Along with the team’s steadily improving win-loss record, its grade point average improved to 3.0, the highest for any University of Minnesota football team. Its graduation rate is also on the rise, and the team has not had any NCAA violations or complaints. In addition, Coach Kill and his wife, Rebecca, have been active in a number of charitable organizations in the community.

Nevertheless, most media attention lately has been focused on Coach Kill’s epileptic seizures and how his team of assistant coaches kept the team operating smoothly when Kill took a leave of absence and was not on the sideline for the bulk of the season.

For those of us who are closely involved with Coach Kill, we understand how his leadership team is turning around Gopher football and operating in his absence without skipping a beat. Nine out of his 10 assistants have been working with Coach Kill for an average of more than 13 years. In fact, this team has been together longer than any major college football coaching staff in the country.

Even if you’re not a Gopher fan, you should be able to recognize that keeping a successful team together for so many years is impressive. During his stint as acting head coach this season, Tracy Claeys (with coach Kill for 19 years) was often asked about his relationship with Coach Kill, and he said that they have been working together for so long that they know what the other one is thinking just by the look on his face. There definitely seems to be a synergy built on team familiarity and tenure that is giving them a powerful advantage.

Now to the research. The performance of Coach Kill’s team led me to find some recent research on teams (“The Hidden Benefits of Keeping Teams Intact” by Robert Huckman and Bradley Staats, Harvard Business Review, December 2013). The authors examined teams over the past seven years in a variety of industries and quantified the benefits of team familiarity.

In a software services firm, for example, they found that when team familiarity increased by 50 percent, defects decreased by 19 percent and deviations from budget decreased by 30 percent. And in consulting and audit teams, high familiarity yielded a 10 percent improvement in performance. In addition, they proved that familiarity was a better predictor of performance than the individual experience of team members or project managers was.

The authors also point out that business isn’t the only area in which team familiarity improves performance. For example, military leaders try to keep special operations teams such as Navy Seals together to deal with dynamic environments, and 73 percent of commercial aviation incidents occur on a crew’s first day of flying together. And NASA found that fatigued but familiar crews made half as many errors as rested but unfamiliar ones.

I know there are naysayers out there who are focused on the benefits of adding members to a team to get fresh perspective. And often it’s just not practical to keep a team together, due to real-world demands such as swapping in skill sets required for a specific project.

However, I’ve also seen the devastating effects on companies that have a revolving door in management. Constant turnover creates fractured visionary thinking, inconsistent follow-through in strategy implementation and a loss of valuable institutional knowledge and memory. This has negative effects on relationships with key customers and causes employees to lose trust in management. And when the management team is always bogged down trying to get to know one another, silos build up around departments, and managers start operating from their own playbook, not a common set of goals and values.

So don’t let office politics, the need to seek team diversity just for the sake of diversity, and the bromide that change is always good drive how you value your management stability. Instead, learn to appreciate the power of team tenure. Place more value on team communication and coordination, of knowing the skills and experience of those on your team, cultivating quicker reactions to marketplace changes and competitive pressures, and building efficient teamwork by not always having to overcome a learning curve. (Another benefit of valuing team tenure is it reduces competitors’ ability to poach key team members).

If your team has been successful together in the past, as Coach Kill’s has, why force change? In other words, if your leadership team ain’t broke . . . why fix ’em?