It's not like the ford guy got a bunch of power he'd never had before- the cable had stretched. He wasn't able to get the engine to full throttle anymore due to the stretch. This hack just lets him use some power that the engine was capable of all along, and used to deliver at full pedal when new. I really doubt the 50hp claim, but I'm sure he got something back.
The same principle would apply to any car with a mechanical cable between the pedal and TB.
Technically, the guy is just re-calibrating the throttle cable. Kind of a lousy way of doing it, with zipties. Some cars have adjustable fittings to make this easier, and his didn't so he hacked it with plastic.
If you try this, don't overdo it. You need to make sure that when you take your foot off the pedal, the throttle body closes all the way- otherwise the engine will never drop all the way to idle, and that could be bad for a lot of reasons.