depends on where the scratch is. if its in your usual field of view, as said, the sand and buff routine will distort it and often times make it more annoying.
Check your insurance policy, they may just replace the glass if its 'chipped'.
Make sure you go with a glazier that has experience with antique car windshields. My dad has the local windshield place do his, the kid they sent out mangled the job BADLY and then ran away. They sent their most Senior Curmudgeon out who knew the difference between putting the gasket on the window vs. in the channel; and how not to mangle the trim, which they ended up replacing. No leaks, no fuss. He was there the better part of the morning (I was working nights at the time so I just came over after work and snoozed on the patio). It was hot, so I got the guy some drinks and a sandwich too.
When a guy cancels an appointment or 2 to unscrew the job he didn't do; it helps to be nice and not take it out on that guy just cuz he wears the same shirt.