  It is usually argued that the Standard Model predicts slow D^0-\bar D^0
oscillations with \Delta M_D, \Delta \Gamma_D < 10^{-3}*\Gamma_D$ and that New
Physics can reveal itself through \Delta M_D exceeding 10^{-3}*\Gamma_D. It is
believed that the bulk of the effect is due to long distance dynamics that
cannot be described at the quark level. We point out that in general the OPE
yields soft GIM suppression scaling only like (m_s/\mu_{hadr})^2 and even like
m_s/\mu_{hadr} rather than m_s^4/m_c^4 of the simple quark box diagram. Such
contributions can actually yield \Delta M_D, \Delta \Gamma_D \sim
O(10^{-3})*\Gamma_D without invoking additional long distance effects. They are
reasonably suppressed as long as the OPE and local duality are qualitatively
applicable in the 1/m_c expansion. We stress the importance of improving the
sensitivity on \Delta \Gamma_D as well as \Delta M_D in a dedicated fashion as
a laboratory for analyzing the onset of quark-hadron duality and comment on the
recent preliminary study on \Delta \Gamma_D by the FOCUS group.
