> Not sure how you can make things like this not to have any lines for what its worth. So not sure what author is going for.
Machine them with wire EDM, like these executive desktop toys? Yes, I know the seamless effect is achieved by polishing the two parts together afterwards, but you can still achieve a practically gapless fit.
One bump in your laptop and you are shit out of luck then though. Removable parts imply that there needs to be extremely slight wiggle room (not to the level rightly criticized by the blog post author, but it cannot completely go away).
