Where the heart is

I'm driving home today listening to an interview on the sports radio, and the person being interviewed (a college student who is going pro next year) say that he was told to follow his heart because "if you follow your heart, it won't lead you wrong". I smiled to myself and nodded. And then I blinked and wondered how true that was. Because there are times where following my heart would have really caused trouble.
So the question is, how far can you trust your heart. Obviously, the answer is going to vary from person to person, but frankly, I'm inclined to believe that no one should ever completely follow their heart with total abandonment. There are times when it is possible to overthink a situation; where it is possible that the best course of action is the least logical. I'm all for that. But if you go around following your heart willy-nilly, then you're going to get into major trouble, or cause irreparable harm to yourself and others.
I guess my advice, then, would be this: always listen to heart, but remember that it is not capable of rational thought. Always listen to your head, but remember that it is not capable of feeling. Find a way to get the two to work together, and when they just can't agree, then pick one and don't look back.