It really does depend on the person. Like take boxing for an example. Boxing is one style and has pretty much universal set of techniques all across the system. But even with the standard four punches there are such a different ways to express those punches. There are people who plays keep away with less dedication to power and more dedication to mobility and distance managing. Then there are people who rushes in and throw compact and powerful punches, and there are so many different type of boxing in between those two types. So how does one weigh a boxer's punch? Do you take the distance fighter's punch or the close fighter's powerful punch? Do you average it out and is it fair to take the average when the close fighter's punch is so much more powerful? How do you even measure damage? By how much it hurts when getting punched by them in a match? That's hardly a good way to measure anything. By punching a machine? Then people would do a huge wind up hammer fist that they do against the arcade punching machine.

This is a question with no definite answers except, it depends on the fighter.

I know of no styles in particular that guarantee powerful strikes. Now there are styles that focus more on striking and train striking more than other aspects like Karate or Taek Won Do but that still will not guarantee that you too will be powerful with your strikes. I do know plenty of people from different styles though that have developed powerful strikes. Not all people develop powerful strikes. But in all reality more power does not make the strike better if you don't know where to hit. If you know good targets to hit then you don't need a lot of power. All you need to learn is where the weak spots are on your target. Saves time in training.

In the 1970's an American martial arts magazine ran an experiment and found that western boxing had the most powerful punches.

In the 2000's one of the documentary TV channels History/Discovery that type of thing, ran a similar experiment and again found that boxers had the most powerful punches.

Bajiquan aka Eight Extremity fist.

I would say muay thai, they do say the kicks can get as hard as a baseball bat..

People strike, not fighting arts. Therefore it varies from person to person.

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