They get pretty serious about the parallel neutral deal here. If the GEC lands in the meter can there can't be a parallel path to the service disconnect enclosure (3 wire SEC in PVC is the norm).
On the line side of the GEC they don't seem to care since there is always some sort of parallel path, even if it is just through the dirt. I will usually see about 2-3a on my GEC and I saw similar currents on the #8cu that comes down the poles from the transformers around the neighborhood. Yeah I know, I have too much time on my hands.
I am still not sure why he couldn't ground the service in one of the disconnects with a #2 and be done with it.