Without wind there is no sailing.
A good sailor knows exactly how high her boat will point into the wind while still maintaining the maximum velocity toward the destination.  This is especially true if you want to get from point A to B as fast as possible and point B is directly upwind.
Achieving maximum velocity toward the destination is a delicate balance between the shortened distance gained by pointing higher and the potential increased speed by falling off.

The chart demonstrates the time you can gain by pointing up 5 degrees, a little over half a minute for a typical leg of a POYC race.  However, if you give up more than 3/10 of a knot, you will have a net loss of time.

Practice, Practice, Practice
The only way to learn how well your boat can pinch the wind is to sail upwind and slowly swing the bow into the wind. When the sails start to luff, fall off until they fill. Work at broad reaching, gybing and running with the wind too.  Take something to measure your speed and see how much speed you give up by pinching the wind.  You should practice in all wind conditions.  During a race is not the time to experiment, so get out and practice sailing to a fixed buoy on the lake.