So you envision the metal firmly attached to the base, like a boulder on the beach, impervious to the ebb and flow of the gelatin?
That certainly is possible, as I have seen some partial evidence like that, but on glass. I am not confident enough to say there is no movement of the metal when the gelatin shrinks around it, but I certainly can see it happening (or not happening, as the case may be).
In fact, the fogginess and "graininess" could be entirely from the micro reticulated gelatin and its effect on light.
Please keep in mind, while I don't accept "grain growth" or "clumping" as necessarily occurring, I do have samples of what I call "micro reticulation" - the term I give it for lack of a better one. Normal reticulation or not, there is something going on that differs from the pronounced ridges and valleys typical of reticulation patterns we are all familiar with.
Unlike Ron who's totally dismissive you're making s sense in your replies. That's because you've seen the problem first hand.
You'll note I've never used the term grain growth myself to describe the increased grain, although it's in some quotes.
The visual effects of micro reticulation are the appearance of increased grain, often slight but at it's worst excessive, there was some discussion on the issue of problems of unexpected grain with Tmax 400 & Xtol on this forum about 6 years ago.* They mirrored exactly what I've seen, and you've made similar posts to that effect in the past referring to post 2001 Tmax fims.
It appears to be caused by lateral stress, and lateral movement, in the emulsion. The effects can often be subtle but they do happen.
Richard* Henry, in his Book Controls in Black-and-White Photography, claimed to have de-bunked the grain clumping/micro reticulation myth, however he only tested one film emulsion, Tri-X in D76, and used a 3.3ºC (68º – 62º F) drop in temperature between developer and stop bath, so hardly conclusive of anything.
A 2005 Dick Dickerson & Sylvia Zawadzki article clears up the myth that developer temperature causes any increased graininess, which is not the issue here anyway as most of us already accept that, but it does indicate we need to look at what's actually happening to the emulsion layer to cause the increased graininess. I've never seen the 2008 article Ron's referring to.
However as Micro reticulation differs from full reticulation as referred to in "Still others confuse extreme graininess with reticulation (an altogether different "dry lake bed" effect resulting from temperature shock between solutions that shatters the gel matrix)." there's not a conflict, but they are accepting that extreme graininess can occur.
The problem is that not all films suffer from the problem , some are extremely robust, a few aren't.
Ian