This is a cool thought. I have been replaying Dustforce lately and it's interesting how "practice" becomes "performance" the moment you clear certain early execution barriers. the goal of the game is to clear all the dust without dying and while there are checkpoints, you don't get that award for using checkpoints so you just need to do it in one go once your happy enough. It's still a bit too seamless but I think this would do great in bringing back the tension in roguelikes... it's so typical to bring down execution requirements low enough that you can learn in the moment but if you let the player to practice all they want and then require them to do a "real" run, well that'd set my heartrate right up