Jerry are you calling the light bulb "drawdown" a reverse charge?
I was taught this is discharge. In the test you described this is normal battery operation and should do as described.
Reverse charging a battery in my mind is hooking it backwards basically charging with current in the same direction as that when battery is discharging. I would think this would destroy not only the battery but also most common off shelf chargers.
Most common cause of cell reversal is discharging battery until lowest cell hits 1.51 and continuing the discharge.
The lowest cell can reverse and will show reverse polarity compared to other cells. This is not recoverable.
Dan Bentler
