Aaah, 1975-1976, I had a look and at the time the 50% level was...

Aaah, 1975-1976, I had a look and at the time the 50% level was $92.50, which was not broken. Gann said that if after the 50% level of support holds then the upward movement in price will go up by a minimum of 100% and if that 100% of the previous range level of resistance is broken then upward movements of price will likely be met with resistance by multiples of 50% ie 100%, 150%, 200%, 250%, 300% etc...

However, I do say that this theory is not full proof. Yet is does put the probabilities in your favour. If one was to spread out this theory amongst 8 different commodities then the overall odds would be in your favour and you would make money even if one or two commodities would fall through.