The inflection property does show in the Write mode properties panel (as well as Engrave). Bear in mind that you can type what ever you like into it, or you can you put the cursor into its text field and scroll up and down. My favoured method for setting these sorts of things is to scroll with Cmd and Shift held - you get very small fractions that way.
Thanks, Lillie, that works, but is very very unintuitive, as visually these 3 dots are not distinct, and the center dot cannot be moved at all with the mouse.
Aligning it with inflection property works very precise and well, as @pianoleo also describes below.
It’s just that Daniel wrote:
Here he talks about directly affecting the inflection property in write mode via the mouse or key commands.
I personally don’t want to hold anyone too much to these words, but currently neither in write nor in engrave mode (where I expected it initally) it’s possible to move the inflection with the mouse or via shortcut, which I find to be a shortcoming.
EDIT: as Leo says, it actually also shows in Write Mode, sorry for my ignorance.