There's plenty of "Scotty haters" on the internet but that guy is a simpleton. "The voltage will equalize"????
What about the effect it will have on the running vehicle's ECU and computer modules when the voltage drops from the dead vehicle being cranked? Then when the voltage spikes when the dead vehicle starts and its starter motor is turned off while the running vehicle's computer is commanding its alternator charging upward of 80%?
Look, the general consensus is that if you're going to jump start somebody, do it with your ignition off.
As for me, I won't jump start anybody (ignition On or OFF) with one of my vehicles. I'm not risking frying a control module or my ECU. I just don't see an upside for taking that risk.
Here's a pretty good write up supporting what Scotty says.
https://ricksfreeautorepairadvice.com/can-a-jump-start-damage-computers/
I would ignore that clown.
#1 - @gew Don't be lazy... please use proper titles.
#2 - Regarding the video: If you want to respond to a video, at least let that person finish. Be honest and show the whole clip without jump cuts. This guy just cut off Scotty mid-sentence, so I have no idea what Scotty was even going to say. All I got was: jump starting a car. One alternator starts spinning, then the other , and then .... ??? Then the guy starts accusing Scotty of saying things I didn't hear him say. Context matters. Picking apart words and slamming people for stupid little inaccuracies, while ignoring the overall message, is petty. I've seen it many times before and it's the same old story. People just trying to leech off Scotty's popularity.
#3 - This redneck actually has no idea what he's talking about.
#4 - Jump starting:
All that being said, I have never had an issue jump starting (even in reverse polarity!). I always do it with the donor vehicle running for extra juice. In my experience, vehicle electrical systems are very robust. They need to be, because conditions are harsh. Electronics components used in the automotive industry are a completely separate grade of product (different from consumer electronics, for example). You can see for yourself if you browse the vendor catalogs. They are certified to tolerate a whole raft of adverse conditions. Over-voltage, under-voltage, transients, temperature differentials, moisture, EMI and so on. And they have to tested as well. One top of that automotive systems have to be redundant, be able to reject noise and corruption, be fail safe, and self-report faults. There is a lot of engineering that goes into it.
I had the same issue with the short excerpt the guy posted of Scotty and I was able to find the video the guy was referring to
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Scotty is giving sound advice and I don't understand what the guy's problem is
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Giving the guy the benefit of the doubt. maybe he doesn't understand that a large percentage Scotty's audience are novices and aren't going to understand what Computer PWM alternator control is or how voltage drops and spikes (surges) can damage circuitry so Scotty puts things in general terms to give those novices an idea of what happens
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These vehicle control modules aren't all that robust. They're computers. Even a static discharge can take them out
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Nobody replaces an ECU or a control module without unhooking the battery negative cable first. Computers don't like voltage surges
On second thought, I'm not giving the troll who made that video the benefit of the doubt. Like I said, he's a simpleton, and like you said, it's clickbait
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https://www.youtube.com/watch?v=pox9nnmkDxQ
Electro-Static Discharge (ESD) is a common thing to expect on an automobile. (I get zapped every time I climb out)
IC's have to be resistant to that too.
https://www.st.com/en/protections-and-emi-filters/automotive-esd-protection.html