1 Jamie: There's a myth that all Scots are engineers. Is there any truth to that?
1 Scottish mining engineer: Nay, tha's a scurrilous rumour spread by the English.
2 Jamie: So what's your profession?
2 Scottish mining engineer: I'm a mining engineer!
3 Jamie: Your wife?
3 Scottish mining engineer: Domestic household and child safety monitoring engineer.
4 Jamie: Your children?
4 Scottish mining engineer: Minecraft and LEGO brick construction engineers!
4 Adam: Myth confirmed…

Surprisingly there's no TV Trope on this. But yes, Scots have been stereotypical engineers for almost as long as there have been engineers, starting way back with James Watt and early steam engines, and also including such luminaries as Thomas Telford and Robert Stevenson. Just look at this list.

EDIT: Uh, yeah, I forgot to mention Montgomery Scott, a.k.a. Scotty, from Star Trek. He was in fact the first and foremost Scottish engineer in my mind when I wrote this strip. I just forgot to include his name when I originally typed up this annotation.