I actually have no idea about any of this... I saw the file said bootrom so i decided to put it on my SD.(Assuming you aren't fucking with us) Part of the 3DS bootrom is unprotected. Dump your unprotected bootrom and compare it to the file. I'm too lazy to do it but who knows?
wouldn't we like KNOW ALREADY if someone took the time to implement the feature?
and no its not the bootrom