I've made his Spanish tortilla once a month or so since that video came out... However, I once dropped the whole thing in the sink while doing the "flip". (Maneuvering a hot cast iron pan isn't easy.) I've never felt more disappointed in myself than I did at that moment; I was making it for breakfast and I basically just turned the stove off and went back to bed. So now I'm always a bit wary when I start on it, knowing that it has the power to destroy me psychologically.
This has happened to me a few times, and I imagine many others!
I bought a “tortilla pan” in Spain which prevents this. It’s basically two pans with an interlock on one side. You cook the tortilla on one side, grab the other pan and lock it on, then flip it over and put the other pan on the heat to cook the other side. Foolproof and worth it when you cook as many as I do!