I have often though why a bank (better if one of the big ones...

I have often though why a bank (better if one of the big ones that Centro already owes money to - CBA) doesn't start buying up massive amounts of shares.
Once up to a certain amount of shares then say to the other lenders "Here is your cash, we are taking over the loan solely".
They can then tell the Centro group that they are not doing the debt to equity swap, maintaining normal payback on the loan and watch as the share price skyrockets.
The shares they bought would then be worth 10, 20 or more times the orginal price netting them millions upon millions.

Of course this could just be a fantasy in my mind to make me feel good that I orginally purchased at 40 cents :)

If this were to happen my money would be on CBA/Colonial.