I still don't quite understand how they arrive at the two arcs. Intelsat IOR at 64E I understand, but what tells them it's that narrow band, and not a band through (for example) Pakistan and the Maldives, which are also not overlapped by another sat? Can someone take the trouble to explain in layperson terms?
There's quite a bit of discussion and accompanying diagrams beginning with TelcoAg's post #3779 a few pages back... explains it very nicely!