I think TRI has the right answer. Apparently, long storage, with the resulting self discharge, does not damage the cells. It is most likely the sudden jolt of the first start which damages some of the cells which have discharged the most. A good grid charge and top level soak for several hours should put you back into good shape. This is also the answer Mike D. gave me once when I asked him.
If you had the HybridRevolt charger, you could schedule periodic charges, say once/week, but I have that charger and I use the other approach
BTW, go to the "User CP" button above and update your profile to include a location, either city or general. You never know when someone who can help is right around the corner.