this is one of those high risk - high reward, high risk - high penalty shots. If you pull it off and save par thats great, but if you miss going for the pin could penalize you 2 more shots. The question is, can I get is close to the pin 70 per cent of the time. If in competitive situation, I would probably hit is hard enough to get on the green and if it rolls 20 feet by then deal with that putt for par. If you make bogey, the error was not the chip, but the shot before it to get you in that situation.