Is core inflation an accurate metric to use when managing the economy?

By defination, core inflation does not measure volatile prices, this includes food and energy prices. If you include it in, then it will be know as headline inflation. I'm pretty new to economics, but i do wonder what is the rational for the Fed to focus on core inflation? Now, the implication is that the Fed probably think they can predict future headline rates better than us and adjust interest rates accordingly. But aside from this implication, does tracking this rate justify the annual increase in oil prices since 2002? Hardly! And this is what i don't understand? How are u going to account for the continuous change in oil prices? Yes, its true that food will account for it somewhat, but if you think about it, the correlation between product and energy prices is largely indirect and thus not so strong. So the annual increase in food prices may not indicate the actual increase of oil in any significant manner. But what makes the Fed think that they can predict where headline inflation is going and base their monetary policies on that pre judgement? Doesn't make sense to me and i'm going to find out more ! hmmf !