Lotta hype over this subject.
If you're banging military brass out of an AR I think it's a waste of time to weight sort. You'll never be able to account for any difference in accuracy.
Differences in case weight are not always attributable to something that would affect case capacity, anyway- like a thicker neck.
I'm sure this is like every other subject like barrel break-in and cleaning that has no clear cut answer other than "it depends".
As a long range shooter I've researched this till my eyes hurt, and come to the conclusion that it mostly doesn't matter as much as other factors like load consistency and neck tension. So I spend my time on the stuff that I think really matters. I weigh cases, but don't sort. If I come across any that are out of "range", I just chuck 'em.