`calculator_spherical_` possible improvement

[mastricker]

Following the discussion on #254 , I am posting an issue here for a possible future improvement:

The calculator_spherical_* does some sorting/adapting on its own during computation. And I think that brakes our logic a little bit of the calculator being a calculator and an adaptor/manager being a filter. This probably does play into the logic of the storage - though I'm not sure. Properties supplied to the calculator do should be writeable at their respective layer, regardless.