Good point, but its usually those that are seriously 'accordioned' like in a plane crash that have serious probs from internal media layers shorting. What I've seen may at worst be a minor loss in capacity - its like the affected area is not longer participating....

Small dent, doubt you'd see anything - there is a separator in between the layers, otherwise the whole thing would be a massive short. You don't see any damage until you damage the file used to separate layers.