See the video below for an out of control teacher.

To see how this relates to dog training, please continue reading

Years ago I was walking down the hallway at my job. A contractor (or supplier or something) tried to hit on me. I had no interest in him, so I just kept walking. As I walked past him, he grabbed my wrist to prevent me from leaving. I already had no respect for him at all. When he grabbed me, my respect for him went into the negatives.
His use of physical force didn't cause me to suddenly become interested in him. I was actually much less interested in someone who didn't have the intellectual ability to maintain my interest with intelligent conversation.

Look at your organization. Who is the actual leader? Yes, you have an official supervisor/manager/president. But who is the actual go-to person in the organization? At parties, who gets the most attention? Who do people gather around? Is it the person who throws his/her weight around? The person who is loud and belligerent, who uses anger, curse words, threats, even physical force to get his/her way? Or is it the calm, intelligent, witty person?

Take a look at this video of a teacher using force in the classroom http://www.youtube.com/watch?v=anLS-sekbQQ. Did he gain any one's respect that day?

Someone who uses a lot of curse words has a limited vocabulary. Someone who resorts to shouting, threats, physical force is out of ideas.

A teacher who uses physical force in the classroom has not been schooled in proper classroom management.

If a "trainer" or "behaviorist" instructs you to shake, yell at, poke, hit, yank, jerk your dog, this person has not spent a lot of time learning operant conditioning.

Imagine if every time you came in late for work, your boss punched you. One of several things might happen depending on what type of person you are. You might quit working there, you might start showing up on time; you might develop an unnatural fear of time clocks, you might punch your boss back. Or you might have a breakdown and attack all of your coworkers.

Excessive force might work on some dogs. But it also has the capability to permanently damage a dog; and it can turn a dog defensive and aggressive.

A lot of trainers talk about dominance, leadership, being the pack leader.
Dominance and leadership are not synonymous with physical coercion and/or threats. Leadership is exactly the opposite of coercion. Real leaders don't use threats or physical force. Real leaders don't frighten people into following them.

You might see a submissive dog roll over on his/her back for a dominant dog. But you won't see a balanced alpha dog push over a dog. The submissive dog chooses to roll over out of reverence and respect for the alpha dog.

So the next time you feel like yelling at your dog because she/he did something that's perfectly natural for dogs, think about that out of control school teacher, think of that crazy boss who yelled till she/he was red in the face, the one whom no one respected. Think about what it really means to be the leader of your pack.