I'm guessing that's in reference to me. What's wrong with suggesting that someone put in extra effort for a successful install? Keeping it simple does not necessarily mean doing things in a half-assed manner. For me, it's worth the exercise of ensuring everything is up to snuff before trying to make something like this work. If that means rewiring the car, so be it. I re-wire all my cars anyway, EFI or not. It's not a big deal.
In case you weren't aware, EFI utilizes digital circuitry which unfortunately is susceptible to RFI/EMI. The Sniper throttle body sits on the intake and is exposed to pulsing magnetic fields all around it - coil, alternator, spark plug wires, etc. When unchecked, RFI can make whatever system you are using go haywire. In mild cases it will make the data stream drop out momentarily which gives intermittent false readings. At worst it can cause the ECU to reset itself at random. Yes, RFI is a known flaw in some of these sytems but if you accept that it's there and are willing to take measures to mitigate it (like rewiring the car) most likely it won't be an issue.
That's why Holley beats it into you about wiring things directly to the battery - they want everything to have "clean" power to prevent RFI from causing problems. If I'm not mistaken, they even say don't wire anything to the positive side of the coil for that exact reason. There's also no direct source of "switched 12V power". What do you do about that?
Beyond that, the main benefit of these systems is the ability to customize and adjust things to a finite level, including controlling timing. Why invest over a grand in one of these things only to handicap it? The "resolution" of the programming is much finer than any mechanical part could ever provide. Again, if you're only utilizing half of the system, it makes little sense to go through the exercise and expense - just optimize what you have already.
Frankly though, that's what happens when people take marketing claims at face value. The manufacturers reel you in with the plug and play idea but that's really not painting the whole picture. Yes, these systems will 'learn' as you drive but if you're just relying on a generic ballpark tune and never lift a finger otherwise you're leaving a lot on the table.
Cheers.