Answer this, what ledger with integrity allows part of itself to be cut off from its main body as in NL's SC2 scenario?
What kind of question is this? "What ledger with integrity"?
"What ledger with integrity allows 800,000 of its coin to be lost to Mt.Gox"
The ledger is neutral. Its users decide on the integrity of its use. If they decide to confer some of the main ledger's unit to a corrupted subchain then they are responsible for the ensuing risks. At the end of the day the main ledger is not affected by the failure of one of its sub ledger.
A ledger that allows those gox coins to simply change hands to those of the attacker, not one where the coins vaporize.