I don't know if it's harder but when you're playing a real person you want to honor their memory - even if they're a criminal or someone that the public loathed. That can be challenging.
“I'm not out there sweating for three hours every day just to find out what it feels like to sweat.”
“A tool is usually more simple than a machine; it is generally used with the hand, whilst a machine is frequently moved by animal or steam power.”