| The mah taken out of each cell MUST be the same, and so must teh mAh | put back equal the mAh taken out in every case.
Really? I've found that my Blips do self discharge somewhat. From your description, I understand that yours do not? I don't buy it.
Sure, LiPo self-discharge rates are pretty low -- but they're not zero. I wonder if the self discharge rates vary at all between individual cells? If they do, even a little, then that would completely explain why occasionally balancing your pack helps extend pack life -- either the cell with the highest self discharge rate gets discharged too deeply, or the cell with the lowest self discharge rate gets overcharged.