Ahhh yesss... the Seleucidsss... mmmm... (slobber slobber, dreaming of varied army compositions).
But seriously, I've read through the entire thread and have encountered no evidence for the metal clad, arrow flinging horror as represented above, but hey I'm only a DIY historian, so I'm no authority.
It's only that I am left with the impression that Drtad is projecting medieval evidence over the ancient period.
For instance, the evidence given for the presence of Armenian Onagers and such, the fame of Armenian engineers in the crusade period, does not leave me to conclude that this would have been the same in the ancient period.
Must have been those damascene sarissa's that kept them at bay ey.