We show that all abnormal parity three-body meson interactions can be adequately described by quark loops, evaluated at zero external momentum, with couplings determined by U(Nf) symmetry. We focus primarily on radiative meson decays which involve one pseudoscalar. The agreement with experiment for nonrare decays is surprisingly good and requires very few parameters, namely the coupling constants gπqq and gρqq and some mixing angles. This agreement extends to some three-body decays that are dominated by pion pairs in a P-wave state.
Theoretical update on two non-resonant three-body channels in charmed meson decays