Keepers in real life make mistakes.. they are in full control of their actions and they are punished for it. In FIFA the keepers aren't making mistakes, it's just shite AI causing havoc. Trying to justify it as realistic is cheap and something i'd expect EA to try and peddle to cover up their incompetence. It's supposed to be a competitive video game, thus balance is more important than realism. When you start trying to replicate mistakes that are outwith the players control - especially ones that give the opposition an advantage, you're going down a slippery slope..