Case studies have been up for awhile, here’s a good source: https://www.nasfaa.org/uploads/documents/SAI_Case_Studies.pdf
This isn’t necessarily true. Many CSS Profile schools haven’t changed the sibling impact on their formulas. The vast majority of FAFSA only schools don’t meet full need, and don’t care what one’s SAI is when calculating financial aid packages.
Fundamentally it makes sense that the poorest students receive the most aid. I do understand why some have an issue with families with kids close together enjoying a possible benefit that other families with kids farther apart do not qualify for.