The compensation will be an active and ongoing one. So if you lock in say 1 bitcoin, and let's assume that it just happened to be at a time when 1 bitcoin was worth $3.80, which also happened to be the price of a Big Mac at that time, then you will receive 100 NDC. Ok, you say, what happens if the value of a bitcoin the next week after that is $7.60? It could happen! In that case you will receive an ADDITIONAL 100 NDC from the system. That's pretty neat. So now you have 200 NDC, which, if you want to, you can use to unlock your previously locked bitcoin in the system.
So when the value of a bitcoin is $7.60 you have 200 NDC and the exchange rate is 200 NDC = 1 BTC.
Then when a week later the value of a bitcoin is $3.80 again, if NDC stays stable that means the exchange rate has to be 100 NDC = 1 BTC, the same as the time two weeks previous when bitcoins were worth $3.80.
So now I can unlock my bitcoin and now I own 100 NDC and 1 BTC, whereas before I owned just 1 BTC. Free money! Also, the remaining NDC I own is not "backed" by anything, because I can't use it to unlock BTC, which means I can't use it to buy a Big Mac.
wtf?
Please read the article I linked to:
https://secure.wikimedia.org/wikipedia/en/wiki/Currency_peg