This technique didnt work at all for my kids. Having any sort of "safety net" at all seemed to prevent any teachable moments. The most important factor in teaching my kids to ride a bike was how long they spent on the bike trying to ride it. I have three kids, and my youngest is too young to learn, so I have one more chance to test my theories.
How long though? I learned the hard way too. It’s worked for lots of people the hard way. But I think there’s lots of evidence now that balance bikes are faster to learn on average. Taking the pedals off is what removes the fear. Steering just happens naturally. Lots of adults who know how to ride bikes don’t even know or believe they’re steering differently than a car, I’ve even had debates with some of them.
I have two kids, taught one with pedals and one without. The pedal-less was immediate in a single day, and the training-wheels pedal bike kid struggled for days until we took the pedals off. Pretty sure my training wheels experience took multiple days, though I can’t remember it clearly.