Restructured how the outputs are shared among the processors.  In principle, with multiple data series it could be faster to split the old way (the first Nout/Nproc files to the first processor, etc) because of the reduction in how often a second state (the t=0 state) will have to be read in.  However, multiple data series is rarely the use-case for me.  Instead, it is easier to have the data files processed approximately in order, so that I can view the progress of the visualization as it is running.