yes, in my experiences, it has a lot better chance of working when you have a solid, hand-written base that it can infer from.. i like to give it feature work sometimes and see what it can do. its hit or miss, sometimes its really impressive and saves me lots of time, other times it majorly gets in the way and is waste of time.

eventually you get a feel for what it has a chance of doing vs. not. and how to prompt it so it has better chances.