On Super Mario Wii U this happens. My daughter used it to see how to get through levels she was having trouble with. It's frustrating to watch, though it showed me I was wrong that levels basically needed the run button to be held to make it across the gaps.

And then you can either accept that the ghost beat the level for you or go back to trying.

But, the thing is it's not very difficult to do this with specific games. You can just record the inputs as they come in and replay those, which is how replays or saved games often work.

Seems like they want to be able to do this for arbitrary games, which requires a much more sophisticated system that can understand what's on the screen, what the goals are, and how to achieve them using just video and audio feedback (and maybe hint documents from the makers).