Retrieving ICX mainnet tokens using ETH private key from toekn swap.

Does anyone know whether the method described in the document below is legit? [https://docs.google.com/document/d/11xNnjZKuOENsBMYnFKHeEYXuV-30o2glwmXs0kUbBAg/edit](https://docs.google.com/document/d/11xNnjZKuOENsBMYnFKHeEYXuV-30o2glwmXs0kUbBAg/edit) Seems very sketchy to be handing over private keys to anyone. I would transfer all funds out before I tried anything anyway.