Lets assume your risk in that position is 10% for a gain of 20%, 10% would be 1R for a gain of 2R. at 50/50 chance of either, expectancy comes out to 0.5R (2R/2 - 1R/2 = 1/2R). Like I mentioned in the earlier post, I would not risk more than 1.25% of my total portfolio value of this trade, 50%...