There is a real life version of this in the bearers cheque or Wechsel (german) or "Bill of exchange", where the wechsel can go from hand to hand, and the intermediate holders endorse the debt. If there are many names on the back of the wechsel and you know all of them (or some of them) to be solid merchants, or there is a bank guaranteeing it, it is just as good as money. The value is the principal less the interest until the maturity, less a little expenses and less the fact that the receiver always prefers money directly.
The point is that you know at least some of the intermediate holders, it would not work with complete strangers.
There is still a systemic risk, for instance if all the merchants trade at different levels of completion of the same end product, they can all go titsup at the same time. In such a scenario, the IOU's will be worth less and the money worth more.
I don't know if ripple can mimic this, but of so, I think it will be useful.