A person has to do the edges? Seems neat, but I'd be curious to see how much setup time there is. If you're going to build a machine to apply roofing, shingles probably aren't a great target. There are a number of very high performance roofing systems that are not shingles. TPU, membrane and there are even a number of excellent spray or roll on liquid roofing systems. If you're in a hot climate some of these white roofs can save a ton on air conditioning. Around a decade ago we put up a white membrane roof on an absolutely gigantic salt storage dome. Just the roof I think was around $3-4 million. I was sceptical at first but it ended up being a very impressive roofing system. I'd take that any day over shingles.