I'm pretty ignorant on this subject, and not a US national, but wouldn't this be a rather good way to eliminate redundancy in similar projects across both agencies at a time when the US needs to rationalise expenditure?
You're right, once you get "Es no posible" you're pretty much screwed regardless of what the issue is or what you have to say. I remember somebody elses number/line getting switched to mine, and being able to demonstate this to Telefonica and just being told it wasn't possible... I had to move apartment in order to get a working line.
My friend did manage to get Telefonica to run a line halfway up the mountain just to his house after his (Spanish) wife spent some time threatening Telefonica with what I think must have been a blood feud... nobody is quite sure what she threatented them with, but it worked.
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