MILWAUKEE, Wisc. — Though President Obama went to Master Lock Co. in Milwaukee, Wis., to champion a payroll tax cut extension and extol the virtues of continued economic vitality, he began his remarks with a memory that evokes - at least for most men – an image of fungal rather than economic growth. “You know, I was thinking about my gym locker in high school,” Obama said to chuckles of laughter from the audience of Master Lock workers.