I would expect “default” to mean the one that the other styles pull from if they have not been modified in a certain way. In fact that’s how it works for typography I noticed already (so at the very least there’s an inconsistency here which is a defect IMO)…
…if I set default to a typo weight of 800 for example, then all the other button styles immediately get the 800 weight even though it wasn’t specified beyond the default style.
As that behaviour is shown for typography, I’d expect the same behaviour in the border radius as another example, and currently that isn’t happening. This is a defect IMO.
Notice in the screenshot below… I have set the typography in default, but not in primary or secondary, but notice they still have the heavier font weight as specified from default. However that is not the behaviour seen for border-radius (set on default but not set on other styles).
Hopefully it’ll be resolved very soon. 
Thank you.
