  We study the decay of fundamental string loops of arbitrary size
L/min(n,m)>>\sqrt{\alpha'}, labelled by (n,m;\lambda_n,\bar{\lambda}_m), where
n,m correspond to left- and right-mover harmonics and \lambda_n,\bar{\lambda}_m
to polarisation tensors, and find that a description in terms of the recent
coherent vertex operator construction of Hindmarsh and Skliros is
computationally very efficient. We primarily show that the decay rates and mass
shifts of vertex operators (n,m;\lambda_n,\bar{\lambda}_m) and their "duals"
(n,m;\lambda_n,\bar{\lambda}_m^*) are equal to leading order in the string
coupling, implying for instance that decay rates of epicycloids equal those of
hypocycloids. We then compute the power and decay rates associated to massless
IR radiation for the trajectory (1,1;\lambda_1,\bar{\lambda}_1), and find that
it is precisely reproduced by the low energy effective theory of Dabholkar and
Harvey. Guided by this correspondence, we conjecture the result for arbitrary
trajectories (n,m;\lambda_n,\bar{\lambda}_m) and discover a curious relation
between gravitational and axion plus dilaton radiation. It is now possible to
start exploring string evolution in regimes where a low energy effective
description is less useful, such as in the vicinity of cusps.
