I don't know why you're talking about loans. Nobody is talking about loans. Legitimate IOU's are backed by actual assets.
*sigh*
If I trust Bitstamp, you trust bitstamp and 8 other people trust bitstamp we can pass a $1 USD IOU from me, to you and all other 8 people with no issue because the actual asset that backs that $1 actually exists at Bitstamp.
*SIGH*
Yep. If someone photocopies a contract 8 times, distributes it among 8 people, and they all sign it, those 8 people could trade those contracts around and just replace the signature with their own.
Each person creating a new IOU before they pass it? I don't even know where you got that from.
SIGH!
Says who? Some gateways will only be gateways and some will actually be market makers as well. This is where you can determine who is best for you to do business with.
If "Market Maker" = "Liquidity Provider", then no. It's not going to happen.
Should not have bothered...
One major drawback of Ripple is that it relies on clients to maintain lists of nodes that are trusted not to collude.
There is a kind of grandeur that creeps into their naiveté. It's like the Voynich Manuscript; everything is so nonsensical that one starts to imagine that it must contain some novel insight that the reader is just missing.
Also like with the Voynich Manuscript, if such an insight does exists, no one can find or understand it.