Sure the systems fail when people are stupid and don't check their system, or, as you said, if they're stupid and they run out.
If you keep an eye on the system and make 100% sure you set it up properly, the odds of it failing and blowing your motor are slim.
Tuning on the bleeding edge with meth is a little crazy, unless you have the funds to fix the motor or a spare motor somewhere. But that's how tuning is regardless of meth. You tune for the bleeding edge and you run the risk of something failing and blowing the motor up. That's performance. You risk shit everyday.
As I said last time we had this discussion, chris johnson of sct told me that he tunes for meth injection. One of the most highly regarded tuners in the country, if not the world. So, you do what you want, but tuning for meth is necessary or there is no point in running it at all.