ShyTorque
Don't get defensive fella, it's a discussion isn't it? & a healthy one at that
I think it's great to practice it, and if you've had the opportunity to do so then great. To answer your question - never, because the airfield I instruct from is rather busy and it isn't allowed, I'd love to try it though.
The good thing about these discussions is that there is no right or wrong answer, not only is the situation a variable, but the pilot also