The neo-Boreals claim to have mass-hallucinated evidence that the Mess does indeed grant backup privileges to all life inside it, but only in direct proportion to their need. For example, an ordinary non-sentient mouse with little sense of individuality or abstraction would have its mind sorted upon the instant of death for any experiences that no mouse has had before; those experiences would be funneled into a collective pool. The next time the mouse population of an area falls below the ideal minimum, a fully mature mouse would be instantiated in a nest somewhere, with a random set of memories drawn from the pool. The neo-Boreals were VERY specific about the particular image of a pool -- perhaps it is related to the Paragnostic Desublimation Pool somehow, the hazy ancestral memory that all Mess residents somehow seem to share?