I'm not arguing that they don't make money from the spread, they obviously do. What I am saying is that an SB will make far more money out of it's customers if they are wrong. The competitiveness of the industry nowadays has reduced spreads to their absolute minimum meaning the revenues available through the spread are greatly reduced.
For example:
If a customer takes a trade at £10pp on an instrument with a one point spread the SB will earn £10 for the spread no matter what. Now if that trader is wrong and he is stopped out at say 15 points away from his entry, which I'm assuming is fairly average for this example, the SB will earn £150. Now as you stated back in post 41, correctly in my view, that 90%-95% of traders lose money, surely it is obvious that the greater portion of the SB's revenue will come from these losing trades.
I realize I'm making some assumptions here but the numbers are so overwhelming I think I am safe in doing so.