I really like this concept. Thanks for making the camera so stable, I normally can't handle first person games.
It took me a sec in the intro to figure out that the grey prevented you from jumping, so it too a few resets to figure stuff out.
I think it has a lot of potential! Controls were pretty intuitive once I got in the flow of things.
The gauntlet was a real struggle. Turns out i'm really bad at giving my future self enough time to do things. I like that sometimes with the right timing you can use sprint to bypass some timing obstacles. Having more than one "perfect" solution is really the way to make things fun.
I think it would've been great to be able to stay on top of past selves' head too. Being able to launch yourself by jumping and then having future self jump on top of your head feels unintended but is a great mechanic! Really gives you some extra distance to break some puzzles.
Oh, and the addition of music would've made this great. Something with a strong beat or cymbal crash every few moments would've made syncing up with my future/past self a lot more fun!
Thanks for the game.