Some people see the S&P 500 index reach new heights and worry they're missing out while others worry there's a crash around the corner. Whichever camp you're in, buying more dividend-paying stocks is probably the surest way to build a portfolio that can outperform over time. Dividend-payers as a class tend to outperform non-payers because these companies are already profitable on a recurring basis. Plus, a commitment to distribute a portion of profits forces managers to think further ahead and exercise more ...