You are not killing the nerves in your shins
The folk explanation for shin conditioning describes an injury, not an adaptation. What actually changes is bone density, and it changes over years.
The story most people are told is that repeated impact kills the nerves in the shin, which is why experienced fighters can kick hard things without pain. That explanation is wrong, and it is a description of nerve damage rather than of training.
What is actually happening is bone remodelling. Repeated moderate loading causes bone to become denser and thicker along the loaded surface — the same adaptation that makes any loaded bone stronger. Alongside it there is a real reduction in pain sensitivity from repeated exposure, which is a normal response to a recurring stimulus rather than the destruction of anything.
The practical consequences matter. Rolling bottles or rolling pins down your shins produces bruising and irritation of the periosteum, not density. Kicking trees and poles gives you an immovable object that returns everything you put into it. And training through shin pain that persists at rest or worsens overnight converts a stress reaction into a fracture.
What works is unglamorous. Kick heavy bags and pads regularly with correct shin contact, over years. Spar with shin guards and check kicks in training. That is essentially the entire programme, and the adaptation is a side effect of consistently training the sport rather than a block of work you can schedule.
Fighters with visibly conditioned shins have usually been kicking bags several times a week for a decade. There is no version of this that takes six weeks.