  (1) KS themselves describe a concrete experimental arrangement to measure Sx2, Sy2, Sz2 on a one-particle spin-1 system as functions of one maximal observable.  An orthohelium atom in the lowest triplet state is placed in a small electric field E of rhombic symmetry. The three observables in question then can be measured as functions of one single observable, the perturbation Hamiltonian Hs. Hs, by the geometry of E, has three distinct possible values, measurement of which reveals which two of Sx2, Sy2, Sz2 have value 1 and which one has value 0 (see Kochen and Specker 1967: 72/311). This is, of course, a proposal to realize an experiment exemplifying our above value constraint (VC2). Could we also realize a (VC1) experiment, i.e. measure a set of commuting projectors projecting on eigenstates of one maximal observable? Peres (1995: 200) answers the question in the affirmative, discusses such an experiment, and refers to Swift and Wright (1980) for details about the technical feasibility. Kochen and Specker’s experimental proposal has, however, not been further pursued, because it does not provide a direct test of NC. Obviously, a measurement of HS measures one orthogonal triple only. An HV proponent might well assume that the hidden state changes from one measurement of HS to the next (even if we prepare the same QM state again) and thus maintain NC. 