Interesting. I've always thought of shards functioning in a similar way: only so much can be used at once, but nothing is really lost forever.
Oh yeah, on a completely different subject, I noticed a really minor connection that is probably just a coincidence, but might be an 'easter egg' on Brandon's behalf. Slaves in the pits of hathsin have to find an atium bead at least once a week to survive. This is eerily similar to the state of the returned, swapping atium for breath. Kelsier's 'surviving' could also be compared to 'returning'. Maybe this even conveys the message that the returned are just as doomed as the slaves, always eventually dying for the people of T'Telir.