Basicly this word 'Martingale' came from the name of some French province in 17 century (the idea and the name).
Later on it was some "issue" between 2 mathematicians by the theory.
After that it came to casino game and it is valid up to now (non-forex practics).
So, as you understand - there is some "gap" between idea/theory and practics in forex.
- "we must be different people from the living around us"
- "we are different"
- "are you martingale?" In that time martingale had the minning:
"you should be different man from the people living around you".
Can you imagine that it exists in 17 century!
For now - we have some slogan as "we are united". But martingale is having the opposite meaning: "we are different". We in our present time - we still can not "break out" this "we are united" to be different. 
We understand now that "we are united because we are different".
And the people from those French provice are already had "we are different". In 17 century!! And it was fully accepted in that time by the other peolpe!
Yes, gap.
Not so many good review and forex ideas. Practics (forex).
Trade 1 or 2 pairs only, and trade only when you are sure that you should trade. It is not "always on the market" systems.
Example with EURCHF - flat for the long time had the meaning that - big breakout after. So, the traders (who are using martingale) - are always checking the market condition to know: do we need to trade this week or not. I used martingale live for the long time.
But sorry - I mostly like this idea from 17 century from France:
We are united because we are different.
