There's some not not too favourable analysis of this scheme from a blogger:

Greek shipping heir Peter Nomikos has a plan wipe out Greek debt. His idea is to buy all the Greek bonds then forgive the debt.

Given that Greek bonds sell for 12 cents on the dollar, on the surface his plan may seem like a reasonable idea. First let's consider the idea, then potential problems.

...

Problematical Math

1. The population of Greece is 11,316,000. At €3,000 per person, Nomikos would need to raise nearly €34 billion. That is far lower than the €283 billion in bonds (at €25,000 per person), but it is hardly inconsequential.
2. Bond prices will not stay at 12 cents on the dollar if the program makes any reasonable headway.
3. Greek banks and pension plans are the biggest holders of Greek debt. I highly suspect neither has marked bonds to market. They certainly have not marked the bonds to zero. In other words there are severe implications should Nomikos succeed.
4. Those depending on Greek pension plans have a vested interest that he not succeed.

I wish Peter Nomikos success, but point number 3 above suggests severe consequences. Points 1, 2, and 4 suggest that it will not happen in the first place, making point number 3 moot.

Read more at http://globaleconomicanalysis.blogspot.co.uk/2012/06/can-greece-buy-freedom-from-debt-for.html