  Conditional elimination of degrees of freedom is shown to lead to an exact
expression for the rate of turbulent energy dissipation in terms of a
renormalized viscosity and a correction. The correction is neglected on the
basis of a previous hypothesis [W.D. McComb and C. Johnston, J.Phys.A v33 L15
(2000)] that there is a range of parameters for which a quasi-stochastic
estimate is a good approximation to the exact conditional average. This
hypothesis was tested by a perturbative calculation to second order in the
local Reynolds number, and the Kolmogorov prefactor (taken as a measure of the
renormalized dissipation rate) was found to reach a fixed point which was
insensitive to initial values of the kinematic viscosity and to values of the
spatial rescaling factor h in the range 0.4 <= h <= 0.8.
