Salon has a disturbing review on the use of pain to prevent the development of secular humanist or liberal tendencies. Various whips and stinging tools are used to hurt infants and children, per the teachings of Michael and Debi Pearl.
How bad an idea is this? Does it really prevent the development of humanist tendencies? We don't really know. What research there is suggests it's probably a bad idea, but the studies are very hard to do well. To get good answers we'd need to randomize children to being hurt physically vs. hurt psychically (time out); the study would enver pass ethics board tests.
In the absence of evidence speculation is indicated. All child raising and puppy training is mixture of positive and negative reinforcement. For some children a 2 minute time out is agony, perhaps some of those children would actually prefer a slap on the wrist. For one child a spanking would be emotionally devastating, for another it might provoke more anger, for another it might be accepted and remembered. I have 3 children and have had two dogs. They are and were all over the map in terms of self-regulation and response to negative (loss of privileges and time-outs for the humans, training collars and in-your-face-yelling for the dogs) and positive (sticker charts, dog treats) reinforcers.
Practically speaking, however, there's a real problem with using physical pain - especially on human children. The problem is the parent.
We have lots of evidence that it's extremely hard to hurt a child in a measured and dispassionate way. Most parents can't manage it -- it takes a lot of anger control. (Same problem with using it on adults of course, as we all ought to know by now.)
The chances that a parent will be very good at using physical pain, and that a given child will actually respond well to it, are pretty low. I'd guess less than 5% of parent-child dyads. (If 1/5 parent good at it and 1/5 child benefits, then success probability is 1/5*1/5 = 1/25 = 4% -- so it's a bad idea 96% of the time).
On the other hand, the timeout by its nature gives both parent and child time to think. As do deferred privileges, etc. Inflicting physical pain is not a good approach, even though most children will survive it. Psychic pain, as in the time-out and the hostage light saber, is safer.
It won't prevent secular humanism anyway. Kids do things like that.