Most demo accounts are significantly different from live accounts. The feeds are different, the spreads are different or non-existent, and they often don't record swap fees. When you go live you will quickly see this and likely lose all your money, or at least not be nearly as profitable.
The easy way to test your theory is to open a tiny account, say $500, and try your hand with that account. If the percentage of returns is the same, then you may be onto something.
I think you'll find that is not the case.
