Hey Jim,

I don't know if there is an accurate way to predict - there seems to be so much variation to longevity and internal chemistry/quality of these packs, even among the same models/suppliers. And it has to do with the way they have been used - if a battery is over discharged once, the unbalanced electrical potential causes the chemicals to start reacting with their container/surroundings. If this happened even to a point where you didn't see any puffiness, it still opened the door for chemical reactions to occur at an increased rate during storage.

Storing in a cool place takes energy from the electrons and slows down the natural corrosion that happens to the packs (kind of like keeping food in a fridge

It is definitely worth a try. Treat the packs like new packs, slowly breaking in and/or cycling for a few cycles until the performance improves and steadies. If the packs were really built well, they may be just fine. Or you may end up using them for practice/warmup packs, or they may be junk.