I agree that we should be able to save failed replays but I don't want the failing system to change. I don't want an F or X to appear.
We must fail (When we do) and then get the same "You failed." Page, and then, be able to save it via f2.
I would get very sad if failing had the F or X letter. I mean, I love the miserable falling notes and the sound effect when we fail. Cause when we fail like that it conveys "LOST".
If a letter was to appear and our scores were to be calculated after the failure, that would convey "FINISHED". Which isn't as good as "LOST".
Sorry if it sounds weird, but I care about how the way I fail affects me; it must make me want to play a thousand times again until I win the thing.