Subscribing to this one as I'm curious about the scenarios you have outlined as well. I was about to contract my trainer with nearly these exact questions. (It's been 10 years since we last trained a pup)
I have seen people talk about +R and use prong collars or E collars. I'd like an explanation on that as well. It just doesn't seem like +R. I'm not saying I don't agree with some of the training tools but I don't see how they can be claimed as +R.
In our case, a High distraction could be a stick or blowing leaf at this point