Originally Posted by Jay Dub
Keep both feet behind the mini and we won't have to worry about "if done correctly". Feldberg could do his same putt one step back.
Actually, if his front foot is off the ground, he couldn't.
I think we're talking about different things.
I'm talking about the rules as they are. There's no rule about keeping both feet behind the mini.
It seems you're talking about a theoretical rule change to create a curved vertical plane* at the mini, which feet can't pass but other body parts can.
(*-my bad geometry; I'm not sure what the correct name for this would be).