I probably made the 2x/3x mistake on my last wheel, just made it 3x out of habit. We'll see how that works out. BITD, we always used 3x on high flange hubs and it worked fine, 4x also works fine. There is no doubt 2x is better though.

Most mechanical engineers are not particularly mechanically inclined. Half of the department works in thermal systems. The other half works on dynamics. Very few profs work in anything mechanically related. Structural design is either in the civil engineering department or the aero department. The mechanical engineering department had a "product dissection" lab for a while. It was pretty embarrassing, to be honest. I think at least 1/3 of the class was taking a bike apart and putting it back together. Lots of ruined tools, especially pedal wrenches.