Years ago, I sat down with Jeremy Grantham in an office overlooking Boston Harbor to not only consider an investment in his fund, but to absorb the insights of a blunt-spoken observer of market risk.

Such blunt-speak, as I've written elsewhere, is a rare trait among the cadres of otherwise high-profile wealth managers whose incentives and survival are often predicated more upon selling hope than speaking to risk—the equivalent of being a whistleblower among a financial advisory complex driven largely by the gathering of fees rather than the reporting (and managing) of risk.

Almost a decade later, I'm still listening to Mr. Grantham and strongly recommend that others do the same.

A Market Bubble of Epic Proportions

Although it should come as no surprise to anyone who has tracked market history as well as market valuations, Mr. Grantham is one among only a handful of credible portfolio managers who have openly confessed that US markets are (and have been for some time) experiencing a market bubble of "epic proportions."

In short: This ought to mean something.

As a keen tracker of both markets and market history, Mr. Grantham is no less confident and no less blunt in warning those who will listen that such epic bubbles always, and without exception, lead to equally epic busts.

We, of course, feel no differently, and have been warning of this bubble-to-bust cycle for years—not as "gold bugs" or "doom and gloomers," but simply as market participants who can both count and read.

Toward this end, we've written at length about the gross over-valuations in risk assets, as measured by every metric known to history.