My most recent run uses Stair skips.

Here's a video on how to do it:

I haven't tested Edith staircase nor Dollmaster staircase yet. I'm sure there's plenty more time to be saved with this.

Edit: It's patched

It's a great discovery.

apparently this got patched today https://caspercroes.itch.io/alisa/devlog/310920/bug-fixes-and-hidden-content-unlocked

The game also fixed the save exploit but the infamous 'Flora softlock' is still in the game which is the one thing I want fixed most