After many months of trying, I have finally succeeded in creating a strategy which survives, and profits, during a full 8 years of back testing on GBPUSD and using a spread of 5 pips to be conservative. And to date it has been profitable on my live account but trading it a half the lot size because of other trades that I am also running on that account. The strategy uses simple MA crossovers for entries and exits with multiple short-term scale-ins reaping in the rewards. The back testing and optimisation enabled me to choose the most beneficial number of scale-ins and TP targets for these.