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An efficiency expert concluded his lecture with a note of caution. "You need to be careful about trying these techniques at home."

"Why?" asked somebody from the audience.

"I watched my wife's routine at dinner for years," the expert explained. "She made lots of trips between the refrigerator, stove, table and cabinets, often carrying a single item at a time.

One day I told her, 'Honey, why don't you try carrying several things at once?'

"Did it save time?" the guy in the audience asked.

"Actually, yes," replied the expert. "It used to take her 30 minutes to make dinner.

Now I do it in ten..."