I've been telling my mother for months that, if her two daughters wear 30" bands, there's no way that she (of similar build) needs a 36" band. She resisted forever but, while doing some other shopping last weekend, I finally persuaded her to try on her actual bra size, not that miserable +4 nonsense. I didn't even bother with a tape measure, just grabbed stuff that was her current band size - 4 and appropriately scaled the cup up. She was thrilled with the fit!

Now I just have to find her some lingerie sales/coupons so that she can start replacing all of those terrible ill-fitting bras!