I'll nominate the below by eyelessgame as a POTM. It's an argument that is elegant in its simplicity and its unavoidability. It's also one I haven't seen before in my many years on t.o. Even better, it's one I think that can be used with a general audience. Alleles are nice and all, but 'before' and 'after' are a lot more understandable.

In article <e707421e.0312191408.224d7660@posting.google.com>, eyelessgame <aamp@oro.net> wrote:

>Piggybacking on Elmer, responding to Jason.
>
>Elmer Bataitis <nylicens@frontiernet.net> wrote in message
>news:<3FE1DCB7.7AC412E7@frontiernet.net>...
>> "Dr. Jason Gastrich" wrote:
>> > eyelessgame wrote:
>>
>> (snip)
>>
>> > > How would you explain the fossilization of pollen, nests, eggs,
>> > > footprints, coproliths, beaches, forests, and raindrops preserved in
>> > > the *middle* of this record (instead of at the bottom), if so?
>>
>> > It doesn't take millions of years for something to fossilize. These things
>> > could have been fossilized during or after the flood.
>>
>> How about you try and think carefully about the questions asked and
>> *then* form an answer to them.
>
>Let me try to help the thought process along. Leave aside the fact
>that quick-forming fossils *look different* from gradual-forming
>fossils, and we find plenty of both kinds. Pretend that we could
>accept that all fossils could conceivably be formed quickly.
>
>Look again at my list. I didn't say "skeletons" or "bones". I said
>"pollen, nests, eggs, footprints, coproliths, beaches, forests, and
>raindrops". Consider the difficulties -- the impossibility -- of
>these forming and fossilizing *in the middle of* a flood.
>
>Let us consider a set of footprints.
>
>You say "These things could have been fossilized during or after the
>flood." Let's look at both possibilities.
>
>Suppose (1) it fossilized after the flood. Then *all layers above it*
>must also have been laid down after the flood.
>
>Suppose (2) it fossilized during the flood. Then the footprinter must
>have lived before the flood -- it certainly didn't *make* the
>footprints during the flood, when the whole earth was underwater!
>Therefore, the rock formation on which the footprints were made, and
>*all rock layers below it*, must have been there before the flood
>first covered that place.
>
>Before you try to object with some special plead about a drowning
>creature leaving its last track underwater, on top of hundreds of feet
>of other flood sediment, think again about the whole list. Does your
>excuse work for all kinds of footprints, for example footprints of
>buoyant creatures? Does it work for beaches? It doesn't work for
>raindrops -- you can't create raindrop impressions underwater, period.
> It doesn't work for pollen. It doesn't work for nests, which are
>often obviously found in-situ on rock formations.
>
>Now, repeat this problem for every single fossilized footprint, beach,
>raindrop, coprolith, nest, and forest. We've found hundreds of
>thousands of these sorts of fossil. And for every single one, either
>all layers above it are post-flood, or all layers below it are
>pre-flood.
>
>This means that finding any two fossils of any of the above at
>different locations in the fossil record guarantees that the layers in
>between *could not have* been laid down by the flood (unless that's
>*all* that was laid down by the flood). And, of course, everything
>either above or below (choose one) this sandwiched area is *also*
>eliminated from being flood-produced.
>
>Multiply this exclusion area by the hundreds of thousands of
>fossilized footprints, beaches, raindrops, pollen, coproliths, nests,
>and forests we have found at all layers of the geologic column (and
>multiply each one of those by all the other fossilized items found
>above or below it at the same site). *None* of the column could have
>been created by a global flood. Every single layer of the column had
>to have been either post-flood or pre-flood.
>
>(Locally catastrophic floods can and do leave layers of sediment.
>Geologists find this all the time. Geologists find, within this flood
>sediment, *no* footprints, beaches, raindrops, pollen, coproliths,
>nests, or forests -- that's one of the ways to know it's a flood
>layer. But they find artifacts above and below flood sediment, and
>that's one of the ways to determine the boundaries of a sedimentary
>flood layer. Footprints on top of it mean that's where flood finished
>laying sediment, at least for a while. Nests at the bottom of it mean
>the flood started leaving sediment here, and the rock below it
>predates the flood.)
>
>So I ask again. Where has any creationist addressed the question of
>precisely how much of the geologic record is the result of the Flood?
>How do flood geologists explain the fossilization of pollen, nests,
>eggs, footprints, coproliths, beaches, forests, and raindrops in
>supposedly Flood-created strata? I ask because neither I nor anyone on
>talk.origins has ever heard of any proposed mechanism that would both
>stand up to a moment's scrutiny and account for multiple layers of
>flood strata containing these fossils.
>
>There are, of course, many other reasons why Flood geology is
>preposterous. It was discarded over two hundred years ago as a
>serious explanation for the geologic column. But please, try dealing
>with this one issue first; when you've exhausted yourself and admit
>you can't explain this evidence, but you still believe in (and want to
>proselytize) a global Flood despite it, we'll then move on to the next
>reason why the flood couldn't have happened. And the next, and the
>next, and the next...
>
>If you want to get a jump on many of the reasons (I know Jason don't
>like seeing more than one piece of evidence at a time -- cf. 'question
>bombing' -- but others who read this thread might appreciate some of
>the voluminous evidence against the Flood) those who want to read the
>evidence should know there is -- shock -- a set of pages at the FAQ
>website, www.talkorigins.org, about this very topic:
>
>http://www.talkorigins.org/origins/faqs-flood.html
>
>for example, the essay behind the first link:
>
>http://www.talkorigins.org/faqs/faq-noahs-ark.html
>
>talks not only about the Flood itself but thoroughly demolishes one
>pious fraud's attempt to develop a superficially rational model of
>Noah's Ark.
>
>eyelessgame
>

-- Robert Grumbine http://www.radix.net/~bobg/ Science faqs and amateur activities notes and links. Sagredo (Galileo Galilei) "You present these recondite matters with too much evidence and ease; this great facility makes them less appreciated than they would be had they been presented in a more abstruse manner." Two New Sciences