Funny. For me when I started with a straight razor I found that one side of my neck grows in an odd direction so I attack it with the grain on the first pass to ease irritation.
I struggled reversing the straight razor and doing an upwards pass on my neck, so it was more a case of shaving down my neck due to necessity. Glad I did though, although I still get some red marking on my neck it’s a huge improvement over the methods of shaving.