He took a couple days doing this, which was shocking to me. Such a waste of time that would have been better spent reading the code and improving any missing documentation - and most importantly asking teammates about necessary context that couldn't just be inferred from the code.
Now I could believe an intern would do such a thing. I’ve seen a structural engineer intern spend four weeks creating a finite element model of a single concrete vault. he could have treated the top deck as a concrete beam used conservative assumptions about the loading and solved it with pen and paper in 30 minutes.