The other article is Sadder But Wiser. It discusses research by Joseph Forgas, a professor of psychology at Australia's University. The article says "Sometimes, he finds, it pays to be sad." Also, " a bad attitude makes us more critical of what we are told and less easily duped."
Here is more:
"Not only can a mild malaise keep us from being bamboozled, but we are more perceptive and have sharper, more accurate recall when we're down in the dumps. The professor tested people on their ability to remember items viewed on a cluttered table. On a dreary, drizzly day, people "had better eyewitness memory for what they saw" than those tested "on a bright, sunny day.""
"The Icelandic mood may have been knocked down a peg or two by the collapse of the country's economy, but that may not be such a bad thing. Could it be that Iceland's positive disposition is what got it into such a mess in the first place? If a dour mood dispels credulity, then where better to peddle monumental scams than in a nation awash in good feelings?"
"The method-acting crowd long ago perfected the technique of dredging up memories of life's awful moments to produce compelling stage tears. A similar technique could have business applications. A maudlin and well-timed musing on the death of your childhood dog could save the company millions.
On the flip side, a salesman looking to close a deal should do his best to induce a warm wave of good feelings. Remember, a happy customer is a rather less critical customer. The customer may want to adopt a crotchety counter-strategy akin to the old saw about not going grocery shopping when hungry: Don't do any sort of shopping when you're cheery."
One more thing. Don't have a nice day.