Thanks! I've heard of JustOneLap but never taken the time to look at it before, looks pretty interesting, i'll go through the site in more detail tonight.
That's exactly my thoughts, the self fulling prophecy part, which is fine as it's just something extra to pull the odds in your favour so it makes sense to use it.
I agree that you can never cater for everything with purely technical analysis, I think you can get pretty close though
As you mention below political events/currency swings can affect things which is a valid concern.
Why not just include the exchange rate as one of your inputs?
It'll react to any major political event just as quick as you could if you were monitoring the situation yourself.