Side note. The mere fact that any aftermarket solution is interfacing with the ECU, means that there is a potential "of messing something up that can kill you". It doesn't matter if it is a piggy-back, inline or replacement chip, a full regression test or ATP would need to be performed to ensure that the entire system has the same expected behaviour as before and the only way to do that is to know the complete functionality and equations inside the manufacturer's SW.
Well i dont necessarily agree with you here. The only damage a engine management mod would do is blow your motor. It certainly isnt going to kill you. You cant tap into the ABS system to work some magic on your brakes and such. Ive been modifying engine parameters since the early 90s and never heard or seen any evidence of aftermarket tuning being the cause of a persons death. Now, we cant control the idiot who points his car into on coming traffic or trees., driving like an idiot in rain or snow, now can we?