What I meant: You cannot simulate a humans decision if he likes red better than green. Or the button on the left better than on the right. For example. That needs to be tested with humans. Indeed. To give some more examples: Also things like whether the person needs more feedback, animations, etc. ...

I must say I'm honestly surprised that the dev team does not use Functional Reactive Programming for their UI code (and things like the building code), as these complex state interactions / asynchronous actions are exactly the kind of use case for this paradigm. I'm pretty sure using that for your G...