In response to the preceding paper by Chýla, the status of some remaining ambiguities in the method of effective charges is reviewed and the specific example of the static potential in QCD is discussed. A criterion for convergence of perturbation theory is suggested, and shown to be satisfied by the recent $O\left({\alpha }_s^3\right)$ calculation of $\sigma (e^{+}{e}^{-}\to \mathrm{hadrons})$ of Gorishny, Kataev, and Larin.

• Received 17 February 1989

DOI:https://doi.org/10.1103/PhysRevD.40.680