[MBlume]

Wait no this doesn't make sense. It's not an 8th decimal of a pound, it's an 8th decimal of what you're measuring. If you're measuring out a pound of Carfentanil you might be off by 0.05mg, but if you're measuring a dose you'll actually take, you won't.

[undersuit]

It still stands that a LD50 of Carfentanil is able to be estimated away because of the change in the precision of a pound.