> if the user belongs to the group
> of the file and group permission is granted, then permission
> is granted.
...
> is there any sensible interpretation of the group outside
> a fossil/kfs/ken's fileserver?
it's just the same: is the user a member of a given group or not?
how membership is established is up to the file server.
the kernel's scheme is trivial (although it could be more elaborate)
but that doesn't limit what other file servers do.
as with the examples you mention, they have only to implement it.
