Phalinks

When performed by an experienced surgeon, the practice is extremely effective, reducing the risk of stroke by up to 70%

They were extremely effective, but at a huge cost in aircrew lives.

Effective as what?

As exercise for health - extremely effective, helping with weight loss and stress reduction as well as building coordination, flexibility and strength.

For building discipline - extremely effective in teaching patience and cooperation.

For self-defense - If taught as a fighting skill, and not as a sport or game, it is extremely effective.

The level of effectiveness of any martial art, for whatever the purpose, is going to depend most on the individual practicing it. The recent winner of the Ultimate Fighting Championship Light Heavyweight Division was a Traditional Karate prctitioner.

Lap-Band surgery is extremely effective. But there are always risks depending on the patient, and it should definitely be something to discuss with a physician.