You need to always remain realistic. Especially when you begin to make statistical claims. There are many things beyond the control of the managment of a company that can create a failure scenerio. I believe that is what Sum is saying. The statistic of 1 in a thousand can all of a sudden apply to established, commercially operating mines.
How can that be, you ask?
Imagine gold dropping back to $500.00 per ounce! A great many operating mines have production costs higher than this. Magically a commercial operation that is/was profitable would join the ranks of the 999 out of a thousand. Please don't tell me it can't happen. It can.... it could.....and it did in the past
Personally I doubt that very much, given the world situation, but that is also what people thought in the 80's when gold collapsed. Always keep your feet firmly on the ground and have a back up plan. Exuberence is usually dealt with by the market and the result is an unhappy one for some investors.
I remain cautiously opitmistc.
pc