Drexlerian nanotech

[Drashner1]

That something may be less efficient in some cases is not the same as it not working. Your characterization also leaves out a lot of details and factors in trying to make its point, including not providing a clear definition of what is meant by 'Drexlerian nanotech' or considering alternate ways of making a ruler or all the circumstances in which you might make a ruler (for example).

I think it's a bit of an overreach to say it 'doesn't work' in any broadly sweeping way, at least based on the information provided here.

Todd