Pipelines and utilities (continued)...
As the author pointed out, a bond investor might not be able to handle the volatility of equities in general. At least historically, and one can go back much further in time than this ~ 14 year study, an investment in these two areas has been much less volatile than the overall market's volatility (look at both best and worst years), has provided investors with much less risk of loss of capital (see both losing periods and largest decline) and got them back to a new high in the value of their portfolio in a far shorter period of time (see time to breakeven.)
This approach will not be for everyone. But for me at least, the odds of achieving above returns while at the same time taking below average risk over the long term (decades) are without doubt in my favour. And decidedly better than owning bonds.