This video gives you a short impression of what is possible (and commonly used) for playing a prerecorded phrase of an instrument or even orchestra LIVE in a free tempo.
I'm a professional keyboard-live-setup programmer and have been doing this for over ten years now. If you want this: feel free to ask me. If you don't like this: I may totally understand your point.
![](https://i.ytimg.com/vi/fPV03F1fUIg/mqdefault.jpg)