Seriously now. I always use my external chargers. I use Nitecore and Xtar chargers. I"m very careful with my batteries, but I don't baby them. I store them in their plastic protective boxes. I just examined my current batteries--chocolate LGs, Sonys and Samsungs (all Mooch-recommended)--intact. Never had a torn or otherwise damaged wrap. I wonder if there are some chargers out there that damage wraps more than others? Am I just lucky?
My chargers are Nitecore, Xtar and Effest. I have lots of different makes of batteries and have to say my LG yellow ones are the main culprits.
I will open up to being a bit ham fisted or heavy handed at times so maybe it's my fault. Sometimes I insert and remove my batteties one handed which probably doesnt help. I will try to be more careful in future.
One thing worth mentioning tho.......my first attempt at rewrapping was a disaster, I over wrapped thinking double protection would be better. A definite no no. That made the battery too thick to slide in some mods. Always remove the original wrap first.