As PZ Myers mentions, Young Earth Creationists absolutely hate being reminded that their World-View is only Seventh Day Adventist propaganda, which originated from their leader's brain damage Hallucinations.
The Seventh Day Adventists were the first modern Christian sect to publish the belief that the Universe and Earth was created in Six, Normal Days.
This concept came from their leader at the time in Ellen White, who suffered a head injury from a rock thrown at her while on the way home when she was 9 years old, by a 13 year old girl, which resulted in brain damage and Hallucinations.
One of these Hallucinations was a time machine ride back to see God create the universe in Six Earth Days.
Her followers all believed her visions to be real truth, as people did not suspect that such visions could be a result of brain trauma and thus false.
One of her devotees (George McCready Price) had some training in mineralogy, but made arrogant claims to being a field geologist, published a pseudo-scientific book based on the Genesis Flood, entitled; "The New Geology" in 1923. Which was defeated by real geologists soon after it was published. Though Price had earlier in 1906 published a paper that he called "Illogical Geology" which was a precursor and alerted genuine geologists as to Price's intent.
Morris went on to create the "Institute for Creation Research" (ICR) which actually does no research, it was an attempt to make Creationism appear scientific, while any donations for their research simply lined the pockets of the members, who occasionally cherry picked genuine Evolutionists papers and comments out of context, to make it appear that they disagreed with evolution. This is the only pseudo-research undertaken by the ICR.
In the extremely poorly educated (still) American Bible Belt regions, Young Earth pseudo-scientific nonsense became extremely popular and the market for publishing and supporting Young Earth Creationism became extremely lucrative.
So much so that it attracted the Australian entrepreneurial creationist, Ken Ham's attention.
Ham made a quick bolt for the US to beat others to fleece the naive sheep of the US Christian belt.
Ham was extremely successful and fleeces the naive of many millions every year and even months.
Now other usurpers like New Zealands, Ray Comfort have decided to make a go at getting a slice of Ham's lucrative pie.
The rest is History.
Yet, even today, their Six Day Creation and Genesis Flood arguments are still the doctrines of the Seventh Day Adventists.
They have not advanced beyond Ellen White's hallucination and George McCready Price's "The New Geology".
Even though they desperately try to distance themselves from and get extremely upset when reminded of the connection (as PZ has noticed), with the Seventh Day Adventist concept, they can never divorce the Ellen White hallucination basis, because they have no way of advancing beyond her hallucination, since there is no evidence for them to make any advances.
Young Earth Creationism will always be simply a conceptual World-View, formed from Ellen White's Brain Damage.
Now You Know All That You Need To Know About Young Earth Creationism.
When confronted by Creationists and asked why I don't accept their arguments? I simply reply:
"Why should I accept unscientific arguments that originated, not from the Bible, but from one woman's nineteenth century Hallucinations, which resulted from her Brain Injury?"
They hate this answer, so don't stand too close to them, I had one foaming at the mouth and spraying me with his angry denial that they have anything to do with Ellen White's cult.
I've also had angry responses online, where I could tell by how badly his spelling became as he attacked me for lying, though again History tells my story, not theirs.
But, history says they are the Liars!
I'm beginning to love my history of beliefs studies.
Hopefully I'll find more stirs in the future, but this is the best stir so far.
Love getting Young Earth Creationists angry.
That used to be my Hobby.
Though they have almost died off completely here.
I sometimes wonder if that 13 year old schoolgirl that threw the rock that hit Ellen G White, found out what that rock started.
Yes, that rock was the initiator of Young Earth Creationism.
Though one could consider that Rock more intelligent than the Young Earth Creationists that it Created.
Aren't I, LOL!