``Think not thy own shadow longer than that of others.''
-- Sir Thomas Browne, Christian Morals. (1682)
Using this optimized algorithm, shadowing experiments were performed on N-body systems in which M bodies move amongst N-M fixed ones. For systems of with a variable-timestep integrator and no softening, our results show that the length of time an orbit is shadowable decreases with increasing M. However, it is unclear whether this is owing to collective effects of interacting moving particles, or whether each particle individually has a ``glitch rate'', causing the global glitch rate to increase linearly with the number of particles. However, for a system of N=65536,M=1 with softening and integrating using constant timestep leapfrog, we were able to shadow the moving particle for two dozen crossing times, which is encouraging.