I can't tell if it's the pics or not, but it looks like the holes are down the middle of the tang and along the sides are more of a dimple, maybe to create an epoxy "pin"? The side holes don't look like they go all the way through the steel. But I would be really concerned about the first few holes especially up near the ricasso! I did a throwing knife years ago where I swiss cheesed the handle to make the blade more front heavy and it broke at the first set of holes at the ricasso. Now I drill my pin holes and fuller out the tang if I want to reduce weight.