Wilson loop evaluations in the stochastic vacuum model

The stochastic vacuum model description of a heavy meson is discussed in the context of a gauge-invariant approach where Wilson loop expectation values appear naturally in the O(v 2) spin-orbit Hamiltonian. These expectation values have been derived elsewhere, however by a procedure whose legitimacy is now placed in question. Here they are derived by standard functional methods with a result that is identical to the previous one. In addition, a full spin-independent Hamiltonian reduction to O(v 2) is carried out.