Hi,
We're getting into tool philosophy here :)
Our vision is that we want everyone to unit test their code. That means power-users (like you), as well as beginners. We know that beginners make mistake, and sometimes these mistakes turn them completely off unit testing.
So this is a choice we're making: We'd rather give up flexibility in our tools, than have people write bad tests and regret it. We believe in starting with guidance to write better test through the tool, than have you write complex tests that are hard to maintain.
Don't get this wrong - we're always on the lookout for more and better features. If you have more, please tell us.
You do have a point about possible usage of overriding APIs, which, if requested a lot, we'll consider in the future.
