You're not comparing power curves to determine who wins races. It's whomever crosses the line first. You will be slower and less stable through the turns if you're on the tops or the hoods. You will be slower, especially with your nose in the wind if you're on the tops or the hoods. Even though you may be producing more power up on the tops or the hoods, it is less efficient, and you will be going slower. As someone else already said, you will also be more stable and less likely to tangle bars when you bump and grind in the drops.