I've worked with a PCB layout designer, and one comment he made is that it's far easier to do a 'by eye' check of, firstly, the virtual layout in CAD, and then the assembled board when things are arranged neatly or at 'nice angles'. Having done some PCB layout myself - mostly through-hole, although with a large number of parts - I never found circumstances in which odd angles made it easier to do the layout. However, I concede it might be for reasons of short traces or making traces certain lengths if required for timing reasons.

Yeah I was thinking the same thing. I imagine finding a part on that board by reference designator is hard.

I can't imagine turning in a schematic drawn like that (parts rotated) for a test in college.