2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/38838We discuss insights that may be drawn from our recent 2 flavour O(a)--improved Wilson quark simulations. We discuss the evidence of the onset of chiral logarithms in the pion decay constant. An overview is given of current extrapolation methods and a modification of chiral perturbation theory is presented as an approach for sensibly extrapolating to the physical quark masses.6 pages, 5 figures. To appear in the proceedings of Workshop on QCD Down Under, Barossa Valley and Adelaide, Australia, 10-19 Mar 2004High Energy Physics - LatticeNuclear Theorytext