The hardest thing to do is trust something mechanical when we are flying blind. If the airplane is flying at night in a storm all the pilot has is his mechanical instruments. If he decides to ignore then he surely will crash. The same is true of mechanical trading systems that have been back tested for 15 years or so. This is why I believe only in a mechanical system. Once it is set up and running a 5th grader can operate it.  So if Matt has done his backtrading properly and never changes the program, then this is the holy grail of a trading system. I would rather fly using instuments than blind.