In my last post I shared some insights from Ben Carlson’s A Wealth of Common Sense, which argues that investors are generally better off keeping their portfolios simple and straightforward. This idea has little appeal for index investors who hope to improve on plain-vanilla funds by using so-called smart beta strategies.

“Smart beta” refers to any rules-based strategy that attempts to outperform traditional cap-weighted index funds. Now more than a decade old, fundamental indexing is the granddaddy of smart beta, while factor-based strategies are the newer kids on the block. In each case, the goal is to build a diversified fund that gives more weight to stocks with certain characteristics (value, small-cap, momentum, and so on) that have delivered higher returns than the broad market over the long term.

Many proponents of passive investing see huge potential in factor-based strategies because they combine the best features of indexing—low-cost, broad diversification, and a rules-based process—with the potential to overcome the shortcomings of traditional cap-weighting. Indeed, many of our clients at PWL Capital use a combination of traditional ETFs and equity funds from Dimensional Fund Advisors (DFA), which have greater exposure to the small-cap, value and profitability factors.

The academic research on factor-based investing is robust and convincing, and building your portfolio using these principles may be rewarding over the long term. Ben Carlson thinks so, too, despite the emphasis he puts on simplicity. But he has some cautionary words for those who are ready to jump on the smart beta bandwagon. “I think these strategies can make sense as part of a broadly diversified portfolio if you know what you’re getting yourself into,” he writes.

A costlier, bumpier ride

Let’s start with the most obvious caveat: smart beta is cheap compared with active strategies, but it’s significantly more costly then traditional ETFs. Cap-weighted ETFs carry almost negligible costs these days, with fees as low as 0.05%, while factor-based funds tend to have MERs in the range of 0.40% to 0.80%. That means they need to deliver significant outperformance before fees to simply break even on an after-cost basis.

Second, any outperformance is probably going to involve a rockier ride. While it’s not true over every period, small-cap and value stocks are typically more volatile than the broad market, so their excess returns may require you to endure more swings in your portfolio. Over the last five years, for example, that standard deviation (a measure of volatility) for both value and small cap stocks was higher than that of the broad market in Canada, the US and international markets. And as Carlson notes: “One of my common sense rules of thumb states that as the expected returns and volatility of an investment increase, so too does poor behaviour.”

Which brings us to the biggest challenge for investors who use smart beta strategies.

The waiting is the hardest part

Investors who embrace smart strategies are usually familiar with the research showing that small-cap and value stocks have outperformed over the very long term in almost every region. But few appreciate that to those premiums can take a long time to show up—and were not talking about a mere five or 10 years.

In his book, Carlson explains that from 1930 to 2013, small-cap value stocks in the US delivered an annualized return of 14.4%, compared with 9.7% for large caps. However, small-cap value lagged the S&P 500 for a 15-year stretch in the 1950s and 1960s, then for seven more years from 1969 to 1976, and finally for a gruelling string of 18 years in the 1980s and 1990s. “Eventually they paid off, but that’s a long time for investors to wait. Patience is a prerequisite for these strategies.”

That’s an understatement. It’s not uncommon for investors to lose faith in a strategy after a year or two. It’s hard to imagine many will hang on to an underperforming smart beta fund as it lags the market for even five years—let alone 18—because they’re confident it will outperform over a lifetime. Almost no one has that kind of patience—with the possible exception of Leafs fans.

“You have to commit to these types of strategies, not use them when they feel comfortable,” Carlson says. “The reason certain strategies work over the long term is because sometimes they don’t work over the short to intermediate term.”

Tracking error regret

Just this week, Larry Swedroe expanded on this idea by looking at the probability that the small and value premiums will be negative over various periods. He demonstrates that there’s a significant chance of underperformance over even a decade or two. “My almost 20 years of experience as a financial advisor has taught me that even the most disciplined investors can have their patience sorely tested by as little as even a few years of underperformance,” he confirms, “let alone a 10-year period without higher returns for value (or small, or international, or emerging market) stocks.”

Swedroe goes on to coin a brilliant term for the anxiety indexers feel when their smart beta strategies go awry: tracking error regret. “These are investors who regret their decision to maintain a portfolio that performs differently than the market. Tracking error regret causes many investors to abandon their well-thought-out, long-term plans.”

The point here is not that you should ignore alternatives to portfolios built from traditional index funds. Smart beta strategies may indeed reward the patient, disciplined investor over the very long term. But no investors should ever feel they’re settling for second-best with a simple solution. In the end, these traditionalists will likely find it easier to stay on course, and may just end up looking like the smart ones.