I'm not sure why (can you clarify *where* in coordinates this is necessary), but I'm not sure it's a bad thing.  In the old `Angle` it didn't matter because there was no concept of the "current" unit, but in the `Quantity` based form, the angle's current unit can be anything.  So I would interpret Angle(Angle(3,'deg'),'hr') as the same as ``Angle(Angle(3,'deg').to('hr'))``. This is mainly useful because you might have the users passing in angles to some object, but you want to make sure the internal `Angle` is always the same (e.g., radians).  Of course you could just use `to`, but this would be a sort of syntactic sugar.