Can someone explain why the battery voltage is so critical at the time of programming with these tuners? It seems there is a fine window of not too low or not too high, why is this? I've also read that funny things can happen if it is not right. Is it a tuner thing or does it have something to do with the ECM? Just seems if there is enough juice to run the electronics and start the truck that that would be enough for the time it takes to load a program?