Axis Location best practice for different master/instance values

Hello, I have a question regarding the Axis Location parameter for masters and instances.

For example, I have three masters: Thin (wght=20), Regular (wght=100), Black (wght=200). I assign the Axis Locations 100, 400 and 900 to my masters. In my instances, though, I find that the Regular is a bit too heavy, so I want to set it to wght=90. What do I do with the Axis Location parameter? Can I set the Axis Location for both the master (wght=100) and the instance (wght=90) to 400? Or how do I go about this? Thanks a lot for any insight!

This is a good question. But is should work like this. But maybe you set the regular master to 450 or even to something that would scale linear to the 90 vs 100 difference? Because the master don’t need to be on full hundreds.