Ok, I found a way to make my stick lifetime longer. But I am not sure if it's 100% legal. Here is the question:

I usually made my sticks with soft wood (pine), that has many grains. Usually, my sticks partially break at the end, in the hook, and so became useless.
I had tried using different glues to fix them, but couldn't find one strong enough. Some time ago, somebody suggested to use a lump of wood. And it worked really fine, it's a good reinforcement.
Actually, I am using the lump in the new sticks, to improve them.

But is it legal ?? The stick is still one material, wood, but it has two pieces.