Is the Holocaust Different?

So this had me thinking a lot in class today towards the end of our discussion, and that format wasn't conducive to what I was trying to say, or I guess, how I wanted to say it (plus, it's a lot easier to articulate in writing). Today it seemed as if we really didn't think that there should be any separation between the Holocaust and other genocides/possible genocides; that we should be able to apply "genocide" a lot more freely and maybe not have the power to sit in class decades later and make gut calls about situations that we are at best marginally informed about.
As for that last notion, hopefully I make some progress towards addressing it in my first (aka real) blog post for this week, but as for the former, I think there is still something that sets the Holocaust apart.
A couple of reasons come to mind: first the fact that with the Holocaust there's no search whatsoever for a "smoking gun." You could say that the smoldering crater of Europe in 1945 was the smoking gun, but even if you didn't have that flair for the dramatic you could also point to any number of speeches by Hitler or others high in the Nazi hierarchy, or just the sheer efficacy of the operation that they ran. Even if there's not one specific, explicit order, no reasonable person could look at the abundant evidence and come to any conclusion other than that the Nazis fully intended to kill every last Jew, Roma, and "invalid," etc. As we're finding out, particularly with the Holodmor, that kind of cut-and-dry is very rare.
Further, though, especially in light of the bureaucratic anarchy that Cannibal Island describes (in which victims are killed at least as much by falling through the cracks as by the sinister movements of the instruments of governance themselves), the degree of systemization - and routinization - in the Holocaust sets it apart from the other two broad case studies we've conducted. Can't you imagine some Nazi bureaucrat getting a demerit because a train of victims was an hour late? (I remember the train scene described in Ordinary Men, but that seems the exception, not the rule, as it stuck out enough to warrant mention in that officer's diary.) Clearly that was very far from the case in Soviet Russia, and my memory of the Armenian genocide offers nothing to suggest that mass killing was so exact there either. There's something genuinely weird about the Holocaust that can't be applied the same way to the Armenian genocide or the Holodmor: all three are horrifying beyond belief - terrible warnings of what humankind is capable of - but the Holocaust (for me) stands alone among the three as, for lack of a better word, unnatural. It doesn't just push me away, it draws me in.
I think what I'm expressing is weakened by the weakness of the "Mad Nazi" model for understanding the Holocaust (and helping the rest of us sleep better), but I think that our study of the Holocaust imparted factual strength to the idea that the majority of the genocide there was precise, accurate, exact - and I don't mean to suggest that that implies a difference of degrees (which is much harder to argue, and I'm not sure I agree with), but it is a deep difference that we should be mindful of.