Because I tested it multiple times this morning at 6am on a Spring card pitcher Sloan. It was almost comical. Once I posted 800 to 1000 more stubs it stopped. When I then delete that amount and put another buy order for a few stubs more, instantly I was 1 upped.
Well, I think that sort of goes against your point. A bot would blindly one up. A rational human would what for that overpriced bid to go through and post a lower one.