Using the RG approach to the theory of fully developed turbulence, we consider the problem of possible IR-essential corrections to the Navier-Stokes equation. We formulate an exact criterion for the "actual IR-essentiality" of the corrections. In accordance with this criterion, we check whether certain classes of composite operators are IR-essential. All of these operators turn out to be actually IR-inessential for arbitrary values of the RG expansion parameter ε. This confirms the absence of the crossover and enables the RG results obtained for asymptotically small values of ε to be extrapolated to the physical range ε > 2.