As much as I dislike arrogance, Airdam's explanation is spot on as he gave the cut locations and techniques to complete the task including the engine running lathe approach. Running the engine at idle will give you a better even cut control on the circumference of the shaft and will be quicker.
the only problem with the motor running is you will need to let the crank cool
a warm/hot crank will have extra tension on the clutch
removing the clutch on a hot crank can be very,very difficult even for experienced people
This sure can be a bias board on people's sensitivity, although my advise might have been stupid because I assumed something that might not be happening, Airdams pointing out the stupid advise being given didnt offend me at all. He didnt make a personal attack on anyone, where other members do that on a daily basis.
Airdam, thanks for the detailed information, as a bad advise giver I'm glad you turned the light switch on so I can see she's ugly, problem is now she knows I'm ugly too