Originally Posted by rusak
This is a basic physics problem. It's not that hard to understand. The extra padding literally results in the force being transferred more slowly and over a greater distance and area. To knock someone out, you need to accelerate their head past a certain limit. The extra padding results in a lower acceleration of the head.
Imagine running into a brick wall and running into a padded wall. The force transfer of your body into the wall will be the same. The difference is basically in how fast your body comes to a stop (decelerates). Against the brick wall the force transfer occurs almost instantly, which results in damage to the tissues, bones, etc. The padded wall results in a slower stop as the padding literally squishes in, which results in less damage.
The limiting factor, is what you can do without breaking your hand.
In the bareknuckle period, few punches were thrown, and half the fight was avoiding a broken hand.
You would be able to hit a padded wall with much more force than a brick wall, without hurting yourself.
There is a reason why early knockouts were virtualy unknown in the bareknuckle era.