The amount you need to change static to rider sag in terms of turns etc is easiest way to have an idea of you need to change springs. Ie would all the way in or out to get rider sag, therefore static being way out, springs need changing.
The reason for a Rider SAG of 30% is to have 70% suspension travel left to compress when you hit a bump. The reason to have Static SAG is to have at least 10% left for the suspension to extend if you ride over a dip and keep the tires on the ground.
4 years ago @andyb wrote a good piece on suspension sag albeit he’s focusing on the rear shock here. https://www.ducatiforum.co.uk/threads/what-is-suspension-sag.77820/
It's an accurate piece but his definitions are wrong. Free SAG and Static SAG are the same thing. He should have said Rider SAG or Total SAG as you have previously written.
