Totally subscribe to its use as a "behavior interrupter" as opposed to punishment. But often times, the behavior being interrupted has a huge emotional charge too. And when "that's three: go to (your room / the [thinking chair] / etc)" gets met with "No!", there's a whole 'nother battle fought to just get the kid to where he/she is to go, and by that time the No Talking (when you're angry) and No Emotion rules for parents are totally out the window and it takes a lot not to let things spiral out of control.
Here's Nev "in her room" just a few minutes ago, doing a great job pushing boundaries, and Mommy's buttons.
There are many more aspects and nuances to these situations, of course. Just want to get this morning's incidentS out here so they are not hamster wheel fodder.
Is it Monday yet?