So Galatea and I were yakking about the new journals (to teach fish finding) that would be inside fished up crates. I pointed out that you could determine at what point loot was determined by opening crates gotten before the patch after the journals were added. Galatea predicted they would use lazy evaluation and not determine loot until it was opened. I predicted that loot would be determined when the container was generated, as since almost all of these crates are opened and looted immediately, there would be no point to not doing so.

After much theoretical jawing about all this, I said, "Fine, I'm going to save my crates until after the patch and then open them, and we'll see." The results? Neither of us was entirely correct.

I saved 100 Curious Crates, and since I was fishing the Steam Pump Debris nodes, I also saved 100 Heavy Supply Crates (which data out at the time pegged at a much lower drop rate of journals). Since it is much easier to get Heavy Supply Crates, and I got that 100 before I got the 100 Curious Crates, I saved another 100 Heavy Supply Crates, but I looked inside them before mailing them to an alt. I opened them all this afternoon after the servers came up.

The results:
100 Curious Crates - 17 journals
100 Heavy Supply Crates - 17 journals
100 Heavy Supply Crates that had already been looked in - 14 journals!

My guess is that a seed is assigned to a container which is used to generate the loot, and that the actual contents aren't stored unless you disturb the contents by looting something from them. Up until this point, these crates have always contained a single item in them. I intend to get my hands on some rogue lockboxes to make sure that the contents are actually saved once something is looted from the container. If it isn't that could be an interesting exploit.

Simple experiment. I have a lockbox on my character on live- I'll get a rogue to unlock it, I'll look in it, then mail it to a bank alt and put it away for at least a week until there's been a server reset on my server and see if the contents changes.

If it requires a loot table change to reset the contents (like your crates) then there's nothing really exploitable. If it just needs a server reset, that's leads to potentially storing up hundreds of lockboxes, checking them after every downtime and only clearing the ones that come up with a blue...

No, what I mean is that since rogue lockboxes often contain more than one item, you loot all but one thing, then log out (presumably triggering the save out function), then log back in and see if the box has the original contents back in it.

Awhile back there was a bug with rogue lockboxes that if you unlocked one and then logged out or mailed it, it would get relocked. This may be related.

I believe I once did this by accident, I had a rogue open a few lockboxes and then had to log before looting all of them (probably out of inventory space or something). Anyway, I was sure I remebered unlocking all of the boxes and looking in them, but at a later date they had all relocked themselves. More to the point though was the feeling the loot had rerolled somehow when I eventually got them unlocked a second time, but without actually knowing for sure what was in each one I just shrugged it off at the time. (/passed the whole thing off as myself going a little crazy.)

-edit, seeing post above about boxes relocking on posting, I guess this could have actually been the cause of all my confusion.

I suppose the experiment if anyone wants to try it is get a large sample of boxes, unlock them, loot a single item from some with 2 items (to check if interfereing with some of the contence "saves" the data for the rest), and then post them all to an alt, tagging those with 1 of 2 items looted, as well as those with 2 items left inside to make sure. Then if you see them relock thats a sure sign, otherwise after a server reset or a week take a peak at them again. This combination should cover most of the potential variables that we can try and play about with, but your 1 lockbox is actually plenty enough to cover most of the matter.

We don't get the patch till today but being an avid fisher I did save 10 Curious Crates without peeking on the offchance they'd have the journal in, nice to know one of them will.

As for the regeneratign contents in my experience this doesn't work. In my old guild we had a running joke passing around this crate that had a bolt of silk in it and the other items removed. We passed this about for four to five months (whover looted the silk would get hacked and then killed irl!!!!) and it never regenerated the leather that was originally in it.

I fished up two Curious Crates in Nagrand the day before the patch and decided to wait to open them for this very purpose. Low and behold when I opened one today (Tuesday) -- it did indeed contain a journal.

If you're looking for an easy to get container with guaranteed more-than-1 loot inside, try the consortium gem bags.

I've pointed this fact out to a GM once

I had a iron bound chest or such, from fishing in SSC (lurker), i took out the cash and left the cloth and leather inside it.
The next day (friday) i looked into it again, and the contents had changed, there was nog a healing potion in the box instead of cloth and leather.

The GM responded that boxes are expected to be looted clean the moment they were opened.
I thought this weird.

Perfect idea, next time i get one with 2 greens i'll let it sit and see what happens to it.

I would only expect the contents to change if for some reason the loot table had changed (as in the case of the crates and the journals). Keeping a bunch of boxes/bags around on the off chance the loot table changes and you get a better item is a really weak and not worth it exploit, there seems little reason for Blizzard to guard against that. To avoid srerious exploits, the contents should be explicitly saved and not change once they have been modified in some way.

I noticed this with the Ticking Present from christmas. I got one on all my alts to get the special patterns, but left the mechanical greench inside since it has a duration but the present does not. A few months later I was going through making space on my alts, and some of the presents had patterns in them again. I don't know what causes the content reset, but I'm 100% certain it does get reset at some point (server restart? content patch?)

I believe the way it works is that loot exists as some form of probability waveform, which then collapses into the proper loot table when the contents are observed.

As for the dead parrot, I'm afraid you got what we call Schrödinger's Crate.