Is the "6.5 peak HP" claim a lie? Technically no. But is it deceptive - absolutely yes! Here's the deal:
The peak HP rating is calculated using the peak watts drawn the instant the switch is closed. In this case, 6.5 HP works out to about 4,850 watts. This is about 41 amps at 120 volts.
But this condition exists for less than only half a cycle (1/120th of a second) after the switch is closed. And a 15 amp household outlet can provide a half cycle surge like this without tripping the breaker.
Now as the motor accelerates the amps, watts and thus HP rapidly drop off. In less than a second the wattage has dropped to around 1,800 (15 amps) or about 2.4 HP. And if you take into account motor efficiency the actual MECHANICAL horsepower delivered at the motor shaft is probably less than 2 HP.
Another point: The motor draws this 6-1/2 HP only the instant after the switch is closed. But since the motor shaft is stationary when the switch closes, the mechanical HP developed the instant the switch is closed is actually ZERO(!).
Gotta love sales hype!