It’s great how instead of sidebearing’s value, you can put in a parent value. And changes apply to the child. But what a child sidebearing is only slightly different? For example: left sides of *h and *l, when *I has small hook at the bottom.
what I actually still wonder about all the time: could it take different values for each master, as it is already implemented (e.g. in the round corners filter). Actually one does not want only +20 in a very light weight, if one has +20 for the black.