The Lions haven't won for two years. And while they played with spunk and energy, they were not going to seriously contest the strongest team in NFL's North, as erratically as it played in the first half.But Singletary and his 49ers will burst into the Viking scenario this week, having emerged from their muddlings of a year ago. On Sunday at the Metrodome, they will confront the Vikings in an improbable meeting of the unbeatens that will match the Vikings' supercharged Adrian Peterson against the 49ers' Frank Gore.In this analogy, the legs are used as the body's heavy artillery, while the hands are the body's infantry. In a military encounter, it is common to use first satelite technology to view the opponents attack and defense cababilities and then use long distance stealth artillery to soften up the enemy and to provide a moving cover behind which the infantry can advance to seize and hold disputed territory. Without the benefit of the artillery, the infantry would take heavy ca