overlapping bl1.bin and bl2.bin files and yet working

[crookies]

sd_fusing.sh is flashing the 2 files ( bl1.bin.hardkernel and bl2.bin.hardkernel.720k_uboot) but if you look at the size of the bl1.bin.hardkernel file is makes 15616bytes.
Yet bl2.bin.hardkernel.720k_uboot is flashed at offset 30*512=15360, so there is not enough place for bl1.bin.hardkernel and bl2 is overlapping.
It works though (meaning that the board boots) but I tried to use the genimage tool in place of sd_fusing.sh to create the sd image and it is impossible because of this overlapping inconsistency.