Trading System with 15 min delayed markets

 
Hello all,

I have a question for those who are experienced with EAs. Do you think it's possibile to build an EA, backtesting it and trade with it in a 15 min delayed market/market data? 

What precaution should be taken to be sure you're not committing bias or logical errors? 

Do you know any CFD brokers who offer trading on stocks, futures and other instruments with real market data ? Of course with MT5/4 terminal.

Thanks
 
think about the premarket stock trading: there are thousands of stocks even blue chips that makes gap 2-3% during premarket and you probably think " damn if I could have entered before the gap"...but the truth is that every broker don't allow to trade premarket and so you are just able to trade when things are already made...BUT

What if I teach you a tecnique to use on a specific broker that allow you to trade a few seconds before the gap and....YOU KNOW IN ADVANCE WHEN PRICE WILL GO 5-20 seconds after you enter?

That's how I trade. I firstly check the premarket insider news on a specific stock, then compare the premarket prices and then wait the entry trigger on the specific broker. Usually 5-10 seconds after I enter I close in profit...just cause the "lag" I have discovered allow me to know when price will go 10 seconds before the gap.
 
Howard Resources:
think about the premarket stock trading: there are thousands of stocks even blue chips that makes gap 2-3% during premarket and you probably think " damn if I could have entered before the gap"...but the truth is that every broker don't allow to trade premarket and so you are just able to trade when things are already made...BUT

What if I teach you a tecnique to use on a specific broker that allow you to trade a few seconds before the gap and....YOU KNOW IN ADVANCE WHEN PRICE WILL GO 5-20 seconds after you enter?

That's how I trade. I firstly check the premarket insider news on a specific stock, then compare the premarket prices and then wait the entry trigger on the specific broker. Usually 5-10 seconds after I enter I close in profit...just cause the "lag" I have discovered allow me to know when price will go 10 seconds before the gap.
So you are saying that a CFD broker with delayed market data could be very good, becouse we could take advantage of that "inefficiency". It seems too easy to be true. Where I wrong ? 
 
Algosupremacy:
 It seems too easy to be true. Where I wrong ? 

It's possible and has been done many times in the past.

But it is also fraud and people have been convicted.