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The "professional" film was designed to give extremely consistent response from roll to roll within a single batch, and very consistent response across multiple batches.
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That professional film required strictly controlled storage and use to maintain that high level of consistency. If, however, those conditions were allowed to vary, the film still performed well, just not with the same roll to roll consistency.
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My impression is that the more modern films don't suffer as much from storage variation as the older ones do, but I've never done the sort of work where high levels of consistency are critical.
Matt, I have a great deal of experience in that sort of thing, and from my experience you are being overly conservative. I don't recall exactly how much film we ran, but it was on the order of miles per day, and printed work was drastically more, easily enough to cave in the roof of a house. We used almost exclusively kodak professional color neg - CPS, VPSII, VPSIII, and Portra 160.
We once got caught with some sort of problem that took a lot of reprinting, and after that we set up a program to screen all of the new emulsions sensitometrically. They virtually never changed (with a few exceptions). But I mention this because it means that we knew what the emulsion looked like when it was new.
Now, in our studio chain, including a traveling "road" operation, we were always getting film back that someone had "found" in the back of a cabinet or in the trunk of a car they were taking over, etc. Because of the unknown storage history, they were instructed not to use it. In our main office we'd pull off a foot or two and print some sensi wedges for an abbreviated screening (similar to what a control strip plot does). Most of the film had presumably been stored in conditions of a typical retail store (in the U.S.), but who knows for sure? Almost always, it was a virtual match for the new sample of the same emulsion. This pattern continued, even when the film was a year or two past the expiration date. And definitely, no one was refrigerating those films.
I should point out that there was some slight fluctuation in these test "plots" but it was within a normal statistical control range. I'm doubtful that regular photographers would have a stable enough process to even be able to detect the occasional emulsion "signatures" that we saw. Certainly these would not have shown on printed work.
I have previously posted results of a "heat stress" test we had done where we ran VPSIII at an elevated temperature for weeks, and then exposed sensi wedges on it. We also ran a couple of amateur films to see how much better they would be than the "delicate" pro films. And we were surprised that VPSIII was significantly more rugged than the amateur films. So a great deal of what we previously had believed about pro vs amateur films was wrong.
Now, if I was planning to use a film 5 years or so out of date, I'd refrigerate or freeze it, but for normal time ranges with the specific films we tested, no - no special storage. Any other brands, sorry, can't say for sure.