Great response! The only thing I would add is that I think Greg is also quite conscious of the "time value of money" combined with the opportunity cost of any given investment. Yes, we could wait for it to come up which it may or may not do, and you could eventually make money, but how much more could you have made if you put the money to use in a more profitable investment instead? Put another way, how much did you lose by not pulling out the money that was left and putting it into a more profitable investment. This is the whole idea behind a good "stop loss" plan. Keep that money working for you!

The thing I always have to remind myself is that the important thing is not how much I have gained or lost on my current investments, but "what do I have right now?" and is that the current best use?