[Al Skierkiewicz]

Kit,
Anything is possible but extremely unlikely in this configuarion. Each of the FETs have diodes across the terminals (drain and source) to prevent backfeeding voltages from damaging the FET. These diodes are capable of 34 amps each. The FETs are also rated for a 30 volt breakdown so with two strings in series, the theoretical breakdown is 60 volts and currents of 102 amps. Since the Chalupas are 12 volt motors and you can't push them to top speed, it is unlikely that the motor is capable of making more than 5 or 6 volts. If you conceptulize the layout of the H bridge inside the Victor, the protection diodes form a diode bridge which then supplies current through the diodes to the power input terminals.
I always suspect metal shavings in Victor failures as you may remember from the Technokats robot in Houston 2003. Even small dust particles from rubbing metal parts will build up a layer of conductive material over time. The humidity of southern Florida may also pose a threat for condensation within the Victor. Best bet is to wait for 15-30 minutes after taking the robot out of doors to apply power.