Yusa buggy?

Because motor rpm isnt the only thing that determines the systems power output.
From what I understand, and there are much more knowledgeable people than me on this board, amps are what cause heat buildup in most ESCs. Also, the amp load capability of the battery can be a major limiting factor in the total power output. So keeping the amp load low is important for efficiency and longevity of everything in the system. Since power is determined by amps and volts, the only way to lower the amp requirement without losing power is to also increase the voltage. It also works the other way, the only way to increase power without increasing the amp load is to increase voltage.

BP revo beat me.