I stutter and I would agree with the not minding part, but I do not mind people that do not know better. As everyone is saying not minding but that is not the same as it being ideal. I don't mind mustard but i prefer mayo. No one wants their sentence finished not because they the other person might get it wrong, but because it is their words and in my case makes me have to restart my thought as someone has added to my conversation. Its not rude it just doesnt help with furthering the conversation.