Why is tempering different from everything else?

[frostburn]

Why are only the up-arrows abstract?

Would make more sense if unison frequency declaration had similar handling to vals.
Abstraction should probably should apply to absolute FJS as well, but then addition becomes even more tricky.
MOS declaration too?

Would lighten up the root context too, most of which likely needs to become scoped to facilitate tempo changes in movement-in-time.