Having the machine code from the ROM isn't the same as having the original assembler files, even if it's close. I would over-comment my assembler just because

Having the machine code from the ROM isn't the same as having the original assembler files, even if it's close. I would over-comment my assembler just because it is an order of magnitude harder to scan over than C code. You also lose all the labels on your subroutines and jmps, all your variable names, all your data block labels.