This is great information - I had never heard of Duqqa (دقة) until reading about it on LTH. I lived in Egypt for some time but never came across it. I have a feeling that I ate it without knowing, as it appears to be used as a garnish more than anything.
What struck me as distinctly not Egyptian (but delicious sounding nonetheless) was using Duqqa in a similar manner to Levantine Za'atar - as a dip with bread and olive oil. There is no olive oil in Egypt. Well there is, but no one, other than the few who can afford it, actually eats it.
After doing some googling in Arabic (love the modern world) I came across some mentions of Egyptian Duqqa and its uses. None of them mention olive oil, but do say that it should be sprinkled on ful, roasted potatoes or even mixed into falafel (pre-frying). That sounds a whole lot more Egyptian to me.
Using it with olive oil is a great idea, but probably one that didn't originate in Egypt's olive oil-meager kitchens. It does however sound like a great and refreshing alternative to Za'atar. And it doesn't probably wouldn't be too bad sprinkled on roasted vegetables either.
Oh, and the recipes described in this thread all seem to be analogous to what I found online in Arabic. So if random internet information (in Arabic) is a measure of authenticity for any of you out there, LTH got Duqqa right.
"By the fig, the olive..." Surat Al-Teen, Mecca 95:1"