The idea that the boat ride itself is the placeholder is very clever - It would explain why those who camp religiously don't seem to see it. However, some have been lucky enough to catch it after a few rides. As someone said, this would really suck if "not riding the boat" was the trigger.
What still interests me is the theory that the pop can "reset", if the pop occurs during a time when the boat is not on the S>N route. For this to have any meaning though, the pop time would have to be a relatively defineable number - i.e. 18-36 hr pop would be way too vague; however, xx # of hrs ON THE HOUR might not be.
25 Vana'diel days pass during one Earth day. If you look at Pyogenes timer, you'll see that the time that the days start is exactly the same day after day, beginning at JP midnight. What this means for this theory is, if the NM spawn is 24 hrs EXACTLY, the NM will never miss the boat - the window would be open at the same time every 25th vanadiel day.
Anything other than that, though, and it's possible the window could be missed. I have a spreadsheet of the Vanadiel calendar which I made for things like this. I'm going to check up on the recent posts and see if any kind of hourly pattern can be made out. I'm choosing to pursue this angle because of ArTwoKay's spotting the NM twice in 4 days, at roughly the same earth time. Seems a bit too coincidental.
Other miscellaneous info-
-The ship routes always occur at the same times every vanadiel day, therefore Dredvodd will always pop within a certain timeframe in Vana'diel. The day/date and moonphase is important, because it gives ppl from different timezones a common reference. Otherwise, the exact pop time isn't real significant.
-Each ship route has it's own data file, which means you'll never see Dredvodd outside the S>N route, or Voldanai outside his route, etc.. Just like you'll never see Orctrap pop on the ferry, or Leaping Lizzy, for that matter - they're totally different zones.
-The Selbina-Mhaura ferry DOES have multiple data files, which each load different NM's. Which NM you get depends randomly on which file loads when you leave port. This is NOT the case for Phanauet Channel - there's just one data file for each route.
Sorry for long post, it's exciting to see so much new info coming in. You all are really helping to pin this NM down. :)
Edit: Hmm. Seems there IS only one data file for all of Phanauet Channel, and not one for each route, I was wrong about that. I guess it isn't so unusual - some zones have more than one map, for instance.
Edited, Sep 20th 2006 at 10:34pm EDT by Turnerbrown