How Do I Make This Hard to Misuse?

Oh, believe me, even when I describe exactly what functions do in the 
header files, complete with examples... they *still* don't get read, or 
people read the first line and ignore the DO NOT DO THIS in screaming 
flashing red with associated MIDI of a screaming police siren (or the 
closest I can get to that in source code). If I make whateveritis not 
compile if misused, it gets hacked by someone else so that it *does* 
compile when misused, because 'that was easier'. (No it bloody wasn't.)

Given that I work in the financial sector I'm tempted to see if I can 
write something which if misused in an unlikely way transfers the contents 
of the misuser's bank account into mine, and document this as a failure 
mode. I'd be rich within the week! ;}