I had planned a post based around the equity curve simulator that I take every opportunity to plug. I do this  because I feel it is really important that people understand the extent to which the variance in their trading account is nothing but cruel, unfeeling, performance-independent chance.

I had only recently noticed, or at least properly appreciated, that the equity doesn’t converge as the number of trades increases. Contrast this to the way that the percentage of heads will tend to 50% as the number of tosses of a coin increases, as the standard deviation=square-root(N*0.5*0.5) where N is the number of tosses.

This non-convergence suggests that we can all trade until the cows come home but the amount of money in our bank will never absolutely reflect how good or bad we are at a trading.  I tried to do something really clever with the maths at this point to reach an important and paradigm-shifting conclusion.  However,I failed, so I am left with only half an argument, half a brain and half a post. I’ve let you down, sorry.

Even then, the money in the bank doesn't accurately reflect how good we are at trading.