Boxing techniques, boxing advice, and boxing instructions to help all boxers train and perfect their boxing skills to become a stronger, more powerful, and faster boxer. Great technique should improve effectiveness and efficiency. Great fighting techniques are focused on improving performance as opposed to be limited by rules and forms. Every fighter and fighting situation is different requiring mastery of many techniques.
There are no such things as the "best fighting techniques", there are only good applications. Technique in itself is not so much what you do, but how you use it.