VitalyBeckman

Some magicians publish their creations, or write books about them, and allow others to use them. Thus anyone buying the book can perform their effect. There are also many illusions that became public domain over the years that are in the grey area. It wouldn't be ok otherwise and best to create your own.

It's more like 3-4 days (at least when you are there in person), the first 2 days I spent filming the introduction, interview, etc. and rehearsing in front of the producers, talking to the judges. The 3rd or 4th day there was a rehearsal live on stage in early afternoon, without Penn & Teller, and later that evening I was performing on their show in front of a live audience and P&T. In the meantime they keep you in the basement greenroom, so you don't see how the other contestants did! And when I was done performing, I wasn't allowed to go back and was sent to my hotel room, again, so I don't see how anyone else did on the show. Of course, that was in 2016, when I filmed virtually recently, it was completely different.

When I was a kid, I was inspired by David Copperfield, Siegfried and Roy, Penn & Teller to name a few :)

Yes could patent a device, but then you have to reveal how it works. You could also patent just the look or design, or claim rights on a certain sequence such as a choreography. Teller won a court case based on that I believe. But you cannot copyright an idea!

Magic is a mixture of art and science. Theater and deception. So one needs to understand how to deceive, and how to tell a story. In deception, you have to understand psychology, control of attention, body language, sleight of hand and magic devices / technique. In theater, you have to understand storytelling, acting, entertainment. Science and physics can be helpful but is the lesser priority.