Not this time! I trust affinity to get that part right.
He said he imported them into a CAD program, though… CAD tends to like to speak DXF or some such, so I might be a bit leery of SVG stroke dimensions coming in cleanly to something like that.
That being said, Inkscape rules, Affinity drools. 
You two are cracking me up! 
I do work in a CAD program (Rhino) where stroke width doesn’t exist - but luckily offsetting curves by X amount is trivial and reliable - so I just need to get used to when and where I need to do it.
@evansd2 you’re right in general that SVG in and out of CAD might be squirrelly - luckily Rhino brought in @geek2nurse 's file perfectly. Now I get to see how its SVG export behaves… Luckily, already a few posts by others here who work in Rhino so most of the gotchas have already been found and worked around. God bless the trailblazers! 
Well, Rhino is definitely no casual app, that’s some serious kit. You’ll probably be just fine.