What would have been truly clever if the documents had differed by more than 0.0147%, all that work and to make it work they change next to nothing.
What if it's an executable or source code, and that 0.0147% change defeats some sort of password checking or other security routine? Maybe it changes a variable (if password=correct set correctpass=1 else correctpass=0) to a constant (set correctpass=1)1? How many bytes would that need?
1 Ok, probably not even close to any RW code but I hope you get the idea. If not, back to remedial English comprehension for you..