In real life, even new objects or constructions are not perfectly straight, aligned, smooth, etc. So if you want to add some more realism to your assets (who doesn't ?!
), then this short tutorial gives us some nice tricks on how to go about that. The only "downside" I would say, is the use of multiple materials, which as far as I know, is not supported in AC. But that's barely a problem, because once the UV mapping is done, you can paint everything in one single texture.
Have fun breaking things !
Have fun breaking things !