Recently, in response to our article on the gold/oil ratio ("What's The Gold/Oil Ratio Telling Us?"), a reader puzzled over the relationship of gold to oil and natural gas. "With natural gas so cheap in comparison to oil currently," he noted, "one can see why Exxon is seeing an investment opportunity in that area."

• Why he's still in UNG
• Bull market benefits base metals, gold and oil
• How (and why) investors should play lithium

If there was ever an object lesson of the advantages of spread trading, yesterday's action in the petroleum markets would be it.

Well, we've been back at the grind for a whole week now after our Labor Day sign-off to summer. Labor Day's a seasonal turning point, you'll recall from last week's piece, "NOW'S The Time (Relatively) For Natural Gas," in the energy cycle. In the fall, natural gas typically gains against crude oil.

A lot of traders and investors jumped the gun on natural gas this year. As it turned out, that gun was held to their heads. And, for many, the trigger was pulled when natural gas prices ratcheted lower over the summer.

• Crazy volumes
• Killer contango
• The 6-month weather forecast?

• Why is Gazprom bothering with prices so low?
• Could the U.S. come to rely on Russian gas?
• When will nat gas prices recover?

• The power of sugar
• Signal value: How far are we though the recession?
• The big caveat

• Low demand
• The importance of rig counts
• Where does it go from here?