No
No, opposite
You have to understand what sensors do to understand what HFI does. The system can take power to generate motion (a motor) or take motion to generate power (a generator). The rotor is the part of the motor that turns. The stator is the part of the motor that doesn’t turn. In order to know which wires to apply power to, the controller needs to know where the rotor is. It can do this by looking at the electricity coming from the motor as a generator. So it knows where the rotor is, and knows which wires to turn on next.
Here is the problem. If the motor isn’t turning, there is no motion, which means there is no generator, which means the controller can’t see the electricity coming from the generator, which means the controller doesn’t know which position the rotor is in, which means the controller can’t know which wires to turn on to start it turning.
So when the motor is completely stopped, we can use hall sensors to detect what position the rotor stopped at, and know which wires to energize to start it. Once we get the motor turning, we don’t need the sensors at all.
The problem is sensors aren’t on every motor, the small sensor wires are fragile and prone to noise, and hall sensors like to break, especially when water is involved. So, whenever sensors aren’t available or aren’t desirable to use, some clever math can allow the controller to briefly pulse energy into the motor to illuminate the rotor (like a light flash in a cave) and figure out where it’s at.
How powerful the motor is, has nothing to do with this. Also, HFI on VESC makes either a lot of noise or a tiny bit of noise. Hall sensors don’t create sounds.