Does experience really count for leaders?

October 17, 2012, 3:58 PM UTC

FORTUNE — I found Gautam Mukunda’s Indispensable to be a bit of a tease. Mukunda, an assistant professor at Harvard Business School, opens by posing some big questions about leadership: Do the times make the person or the person the times? Can one leader ever be truly indispensable? How can we best evaluate candidates for leadership, be they potential CEOs or potential leaders of the free world?

If you’re looking for clear answers to those questions, you won’t find them here. (If you happen to know where they can be found, please let the rest of know.) What you will find is an intriguing new theory about the various paths leaders take to the top of their organizations, and what those paths can tell us about any one leader’s potential to have an outsized impact, for good or for ill.

Mukunda’s key concept is something he calls the Leader Filtration Process (LFP). Some LFPs are tight, such as those employed by the military, the government of Singapore (who knew?), and most famously in the business world, GE (GE). The goal of a tight LFP is to produce — patiently, deliberately and dispassionately — a pool of carefully vetted potential leaders, any one of whom could capably fill the top spot.

“Removing any single candidate would have little impact” by the time the filtering process has run its course, Mukunda writes. “He or she would be replaced by another, highly similar, candidate.” Which leader ultimately gets the nod, in other words, may not make a whole lot of difference.

Other LFPs are loose. Think, for instance, how we choose a president, or how a VC vets an entrepreneur. There’s still a process but it’s less restrictive, and more vulnerable to circumvention by unfiltered outliers. Consequently a loose LFP is more likely to “produce a broad distribution of victors if it could be run many times over. The outliers could potentially be very far away, allowing for the possibility of winners who are radically different from other candidates.”

Different processes predict different outcomes. In a tight LFP, you’re almost certain to end up with a “modal leader” who is unlikely to shock or surprise. Loose LFPs can produce “extreme leaders,” which might be exactly what your organization needs. But tread carefully: “Extreme leaders will tend to be great successes or great failures. Few will be quickly forgotten.”

For a business book, Indispensable concerns itself an awful lot with politics and history. There are entire chapters devoted to Thomas Jefferson (filtered), Abraham Lincoln (unfiltered) and Woodrow Wilson (unfiltered). Mukunda also contrasts the unfiltered Winston Churchill with his filtered predecessor Neville Chamberlain, Britain’s great appeaser, arguing in Chamberlain’s case: “(I)t seems more than likely that no plausible alternative would have done much better”.

The only CEO who gets anything approaching equal treatment is Al “Chainsaw” Dunlap, whom Mukunda describes as “an almost too perfect encapsulation of the potential downfalls of choosing an Unfiltered Extreme.”

You might appreciate the history lessons, or you might not. Personally, I’m not sure a B-school professor is the best source for insight into Lincoln’s mental health. Is the evidence that he suffered from depression really “quite clear cut?” Same goes for Jefferson’s role in the Louisiana Purchase, which Mukunda dismisses as “minimal.” It might occur to you, while wading through the middle chapters, that the author is an unfiltered historian, with all that implies.

In any case, Mukunda maintains that U.S. presidents make especially good test cases for his theory. Some would-be presidents work their way up one elective office at a time, methodically gathering the backing of voters and party elites. These are classic filtered leaders. Unfiltered leaders tend to skip the winnowing process “and try for the presidency directly.” So what does the historical record tell us about filtered presidents, unfiltered presidents and the success of their administrations?

Quite a lot, Mukunda argues. First, he comes up with what he calls a consensus ranking of presidential performance. (Some readers may question the consensus.) Then he classifies each president as filtered or unfiltered, using eight years of “national prepresidential political experience” in elective office as the dividing line.

For the record, neither Barack Obama nor Mitt Romney is included in Mukunda’s data set. But when I interviewed Mukunda in August, he described both as unfiltered candidates. Prior to winning the 2008 election, Obama’s political experience was confined to the Illinois state legislature and a single, unfinished term in the U.S. Senate. And while Romney served a full term as governor of Massachusetts, Mukunda argues that he has less relevant experience than any Republican president has ever had before entering the Oval Office, and less than any president of any party except Woodrow Wilson.

What Mukunda finds is pretty much what LFP theory would have predicted. Seven of the top-10 presidents were unfiltered leaders by his definition: Lincoln, FDR, Washington, Teddy Roosevelt, Wilson, Eisenhower, and Polk. But so were eight of the bottom 10: Harding, Pierce, Andrew Johnson, George W. Bush, Grant, Fillmore, Tyler, and Coolidge. Win or lose, Mukunda is telling us, choosing an unfiltered leader is a high-stakes bet.

Our Weekly Read column features Fortune staffers’ and contributors’ takes on recently published books about the business world and beyond. We’ve invited the entire Fortune family — from our writers and editors to our photo editors and designers — to weigh in on books of their choosing based on their individual tastes or curiosities.

More Weekly Reads