I have since switched over to the svn checkout of basemap, and this issue
appears to be 'fixed'. While readshapefile() does still load all of the
data, it appears that .set_axes_limits() automatically turns off
autoscaling. This should cut down on much of the "odd" behaviors users
would encounter
I did some more digging and I think I have a hypothesis for what is
happening.
There is only one main difference between a call to .drawstates() and
.readshapefiles() with respect to loading and plotting data. .drawstates()
loads *only* the line segments that coincide with the defined map
boundar
