I understand where your coming from Peter I'm exactly the same.
I have used smacking on my daughter who is 5. One day I asked her to do her room, she said straight up NO. I turned around said Brandi youv'e made the mess I'm telling you to clean it up if I come in and you haven't started you will be smacked. I gave her 5 minutes and returned, no progress. I said Brandi why won't you do as your told would you rather be smacked or tidy your room, I WANT A SMACK, was the answer, so I gave her a few decent ones, enough to sting my hand a bit, and she just bit her bottom lip and glared in defiance even managing to hold back the tears. I had to leave the room so she couldn't see me smile and I was actually a little proud of her. I smack a lot less now but sometimes it's still affective..
I used to play up for my mother and if she was at the end of her tether she would always use the wait till your father got home line. This would only make me worse because I then knew what I had coming, and my Father often crossed the line between discipline and physical assault.