Re: Interesting footnote
Who you calling an EBCDIC!
(Just kidding of course). Having seen something very similar happen at a large 3 letter NGO based in the land of gold and chocolate... I can see how this sort of stuff happens when code gets outsourced, then offshored and little bits of knowledge get lost along the way and then one day. BAM.
Twice in my career I've found such errors when inspecting code trying to debug it and finding serious errors in financial calculations. Both times the project management were in shock and took remedial action but hushed it up from going higher up the chain out of embarrassment.