My current girlfriend straight up confronted it, made my life a whole lot easier everyone’s different. If I’m having a very bad stuttering session someone finishing my sentence is amazing. It’s like anything it’s preference. A lot of people on this sub seem to put in rules, which is absolutely fine but it’s all subjective to the person. Something I think we all pretty much agree on is don’t interrupt half way through the stutter, means we have to start again and it’s not fun.