  Wide area cosmological surveys enable investigation of whether dark energy
properties are the same in different directions on the sky. Cosmic microwave
background observations strongly restrict any dynamical effects from
anisotropy, in an integrated sense. For more local constraints we compute
limits from simulated distance measurements for various distributions of survey
fields in a Bianchi I anisotropic universe. We then consider the effects of
fitting for line of sight properties where isotropic dynamics is assumed
(testing the accuracy through simulations) and compare sensitivities of
observational probes for anisotropies, from astrophysical systematics as well
as dark energy. We also point out some interesting features of anisotropic
expansion in Bianchi I cosmology.
