On the Internet, nobody cares if you're an imbecile

This whole thing of "On the Internet, nobody knows you're a dog" has gotten a little out of hand and has morphed into "On the Internet, nobody cares if you're an imbecile."

~ http://www.weeklystorybook.com/comic_strip_of_the_daycom/2012/05/ask_clique_and_claque.html

I was grading a student's drawing I noticed that the arcs didn't seem to join flush to the horizontal lines. 

Zooming in and sure enough.

A look at the top revealed a gap and the lines which should have ended at the horizontal lines extended beyond.

When I asked the student why the dimensions were off he responded:

I was just eye balling, I didn't realize how serious it was to follow the units, I thought they were just reference

I didn't and still don't know how to respond.  He's an Engineering student.  In my mind that means something.  All manner of snarky comments suggest themselves from a lament about American higher education to the hope that he, like many students, will change his major to avoiding domestically produced goods.