Thought I'd pass this on, after having discovered the "feature" (latest firmware):
If I press "CLEAR" in the stick calibration menu, it will wipe the stick calibration. From now on, we're in playstation-controller mode where the smallest movement gives full-tilt input.
This makes some weird sense - the "clear button" does what it's supposed to do.
What does not make sense is that it bypasses the "SAVE" button. It results in the same button "click" as pressing clear in the main system menu, there is no other warning or confirmation.
If I know about this, it's no big deal. If not, it might cause some nasty surprises.