[fiachamp]

IMO - its a question of exposure and convexity of your positions moreso than risk. Risk involves predicting the chance that different outcomes occur and...no one is really good at that. However, do you feel comfortable exposing X% of your total assets to the upside of Google growth? If you think in terms of controlling your max loss per opportunity and making sure you're in ones that have significantly more upside than exposure, you don't need to predict correctly quite as much.