Let me give you a quick example: let's say investor A buys 1000 shares: 1000 shares * 0.1BTC/share = 100 BTC. I would invest approx 66 BTC, and leave the 34 BTC in the account. These 34 BTC would be available to pay the person back if he or she decided to sell some of their shares back to me at 0.05 BTC each. 34 BTC / 0.05 BTC/share = 680 shares available for sell back at 0.05 each. So in the case of a catastrophic failure where all of my investments fail, the most that any investor could lose would 66.667%. People would not trade between these walls because doing so would cause them to lose a great deal of money (approximately 67% for each buy/sell/buy cycle). This is ensured by the fact that my buy and sell prices are fixed.
No, sorry, but I like to understand -and I can't get your logic to make sense to me.
So you say, out of 100BTC invested I am only risking 66. That translates to: to risk 66 BTC with you -since to gain interest one has to risk in the first place- I have to give you nothing less than 100 BTC! Why on earth should I want to do that? If I want to only risk 66 BTC with you, fine, allow me to only give you that 66, use them fully, and let the other 34 stay with someone I trust even more than you, i.e. myself. Hope you get my point