Here is the thread where I discussed it in more detail - from post #8
http://forums.overclockers.co.uk/showthread.php?t=18375212&highlight=usury+username_freakbro
As posters like Dolph were quite pejoratively vocal about (unfairly imo), they are still getting a return on investment, just that it is a different mechanism than 'interest'
But that is by the by, the more fundamental principle I was interested in with ethical banking is the premise of shared risk of the investment, where both the lender and borrower have an invested interest in the repayment of the loan.
This should help promote responsible lending, something our own system severely lacks.