Knowledge workers are so central to today's global economy, it is easy to forget that the term is only several decades old, introduced by Peter Drucker in his 1969 book "The Age of Discontinuity." Before World War II, hard work and social standing were valued more than raw ability in all but a handful of professions.

Calvin Coolidge reflected the realities of his 1920s society when he pitilessly observed: "Nothing can take the place of persistence. Talent will not; nothing is more common than unsuccessful men of great talent. Genius will not; unrewarded genius is almost a proverb."

But in a knowledge-based economy, "unrewarded genius" more often describes the moderately successful, rather than those who fail altogether. There probably has never been a better society in history than ours in which to possess raw talent in creating, analyzing and synthesizing information.

What is the best way for talented knowledge workers to raise their odds of success? Tenacity is vital, of course, but balance matters too.

Now, this is not a call for the "well-rounded individual," or sanding off rough edges. Unusual ability is a powerful competitive advantage. And as Drucker has written, the critical aspect of managing employees (or yourself) is to discover what they can do well, rather than worrying about what they can't.

Yet people with outsized abilities often have outsized frailties. They may resemble a high-powered but badly wired sports car, like a 1970s Jaguar, whose electrical system was so unreliable it was nicknamed the "Prince of Darkness."

Talent will win more often than not if it can stay on the racetrack. The race car doesn't have to be as reliable as the family sedan; it will win races if it is more reliable than other race cars.

Your progress will be smoother and faster if your secondary skills are developed to the point where they are not a liability, and if you avoid the temptation to be enamored with your abilities as an end to themselves, rather than as a means to a goal.

Yet this temptation bedevils talented professionals across industries: the NFL wide receiver with world-class speed who doesn't bother running accurate routes; the brilliant software engineer who becomes obsessed with writing elegant algorithms rather than solving customers' problems; the wascally wabbit who antagonizes hunters and other creatures in the forest, rather than being content with frolicking.

Contrast that with the home run slugger in baseball who labors to be an adequate outfielder, or Winston Churchill, a visionary leader who was quite able as a manager, especially in contrast to his creative peers.

What's the best way to develop these skills? In his autobiography, "My American Journey," Colin Powell writes of a personal improvement tool he developed midway through his career.

First, grade your various attributes on a 1-to-10 scale (i.e. creativity, discipline, selling, operations, interpersonal skills). Say you're a marketing executive, and are a 9 in creativity, and a 3 in operations. Clearly, creativity is what you are best at, and enjoy doing the most.

The temptation is to try to improve your 9 in creativity to a 10. But Powell points out that trying to improve your strengths is often the wrong way to go.

Why? Improving your creativity from a 9 to a 10 will have an incremental impact on your overall performance. Moreover, "perfection" is a nebulous goal, whose pursuit can become obsessive or self-indulgent.

Instead, Powell preaches improving your weaknesses as a "force multiplier." Your ranking of 3 in operations can, with effort, be improved to a 6. By doubling your ability in a weakness, you've massively improved the total strength of your "system."

This approach has much in common with the principles of Eli Goldratt's "Theory of Constraints" (as made popular in his business novel "The Goal") for identifying and resolving bottlenecks that constitute the weakest link in your workflow.

Here are my five rules of Career Management for Non-Dummies:

1. Cultivate your strengths, but don't obsess about them. The pursuit of "perfection" is pointless if complementary attributes remain underdeveloped.

2. Keep your eye on the prize. Don't fixate on what you enjoy doing well to the detriment of what you are trying to accomplish.

3. When possible, find roles that leverage everything you do well. This requires a realistic assessment of your skills and the factors critical to success in the role and organization.

4. No pain, no gain. Don't ignore opportunities to step outside your comfort zone and grow new competencies. Your current strengths should be a starting point, not a line of defense for your ego.

5. "Competent" is not a dirty word. It is unlikely you will become great at tasks you don't do well or dislike doing. But achieving adequacy will allow your strengths to shine and will have a transforming effect on your career.