Yeah, this is a great topic!! I have been a Celtic's fan since the late 1970's and my top "what if" moment is what if McHale and Chief hadn't both gone after Kareem's missed free throw at the end of Game 4 in the 1987 Finals and knocked the ball out of bounds which let the Lakers keep posession and set up Magic's famous baby hook shot to give them a 3-1 lead and basically won the title for them. I don't fault McHale and Chief for this because they were each trying to get the rebound and they certainly didn't know they were messing each other up going for the rebound-plus McHale was playing great on a broken foot which shortened his career. But I think we would have had a great shot at winning it all in 1987 if McHale or Chief had secured Kareem's missed free throw and the series would have been tied 2-2 with Game 5 in Boston. As somebody else mentioned, Bird almost bailed us out with a 3 pointer that just missed going in. Coming back from 24 points in Game 4 last year helped me get over Game 4 from 1987 but I will never totally get over it.