For those who play their games on Steam, there’s a simple way to create you’re own checkpoints (in a way).
As you can see in this post by @ClaimedMinotaur, you just have to copy elsewhere the state file (for example before a major branching or a minor one if you’re just curious to see the different text flavors) and when you want to restart the game from there you just have to paste it again in its original folder.
I know, it’s just a workaround and a bit intricate at first, but I guess it works pretty well if you want to see small text variants without having to play the entire game again (or if things get messy and you don’t want a fresh restart!).