Those who say it didn't are, and have been known for a while as "the revisionists"

And that is precisely what I see as dangerous. Because assimilating the terms "Holocaust denial" and "revisionism" plays into the hands of the Holocaust deniers.

The danger is that every time some historical investigation throws up evidence that some aspect of the accepted narrative is wrong - even relatively minor details - this will be presented as somehow strengthening the case of the Holocaust deniers. The logic being that in this instance "revisionism" has been demonstrated to be correct - and "revisionism" has been identified as equivalent to Holocaust denial.

Sorry if I annoy you with this, lox. I don't think the distinction I am making here is in fact pedantic.
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One example of a situation where a kind of revisionism has been relevant is the one which has insisted that more attention be given to the genocide of Roma (gypsies) in the Holocaust.

I remember talking to someone who had told me how, on a visit to a Holocaust memorial, he came across someone weeping with indignation at the fact that this genocide was mentioned alongside the Holocaust of Jews, because she felt that somehow this was an intrusion and an insult.

The point is, there is scholarly history, and there is popular history, and sometimes the popular history fails to take into account aspects of the scholarly history - and the popular history is the one that can shape the world.