Surely he's digging a hole for himself as if/when they do take it he will still owe the outstanding balance - including any accrued/capitalised interest/arrears? And if/when the lender chases the debt through the courts isn't it likely that a judge might take a dim view of him not making even token repayments along the way?
If you're on the dole the courts won't make you pay anything. I know two mortgages that are months in arrears and they just keep sending statements from one department and threats from another. The people want the properties repossessed but the banks are very slow. Even though apparently the sub primers are very active one of these I've mentioned is sub prime.
For people whose credit rating is shot anyway, people are beginning to learn that they've nothing more to lose.