  New arguments are presented in favor of the infrared finite coupling approach
to power corrections in the context of Sudakov resummation. The more regular
infrared behavior of some peculiar combinations of Sudakov anomalous
dimensions, free of Landau singularities at large Nf, is pointed out. A general
conflict between the infrared finite coupling and infrared renormalon
approaches to power corrections is explained, and a possible resolution is
proposed, which makes use of the arbitrariness of the choice of constant terms
in the Sudakov exponent. A simple ansatz for a `universal' non-perturbative
Sudakov effective coupling at large Nf emerges naturally from these
considerations. An alternative evidence for an infrared finite {\em
perturbative} effective coupling in the Drell-Yan process at large Nf (albeit
at odds with the infrared renormalon argument) is found within the framework of
Sudakov resummation for eikonal cross sections of Laenen, Sterman and
Vogelsang.
