WOW all that for a stuck case?
Not quite. In the first instance, unless you can detach the case from the expander, you can't get your die back. After that, it is usually a case (pardon me) of wanting to get the expander button back. Usually this requires sawing the case in two, and even so, there is enough wrong with the case that I'd chuck it anyhow.
Changing the Subject:
Dick's data is fascinating, and I have no ready explanation. Nor, at least intuitively, am I prepared to accept (or reject) TonyD's hypothesis that sizing causes a case length growth because of metal flow (in essence, a form of hollow-tube extrusion).
Here's what someone should do:
From time to time I form cases for a wildcat called .308 x. 1.5" (a/k/a .308 Barnes). This round shares both the head and neck/shoulder dimensions of a .308 Winchester (7.62 x 51), but is shortened to an OAL of 1.5". (Interestingly, it turns out to be the predecessor of the short stubby rounds now considered to be so inherently accurate, but was designed way back in 1961.)
Forming involves setting the neck and shoulder back just a tad over half an inch (if you use .308 brass, which involves a lot of effort; about 0.3" if you start with .300 Savage brass, which works a bit easier). You do this by slowly forcing the .308 (or .300) case into a series of forming dies. When it comes out of the last die, it looks like a stubby .308 with a very long neck.
What I've never done is to measure the OAL of a case that has come out of the last forming die and before it goes into trimming. Based on Dick's data, you would expect this to exceed the starting OAL of the case by a significant amount, and, if so, this might validate TonyD's hypothesis.
I still believe that if you compared the before and after firing case OALs for cases that were neck sized and cases that were full-length sized, you would find a much greater disparity, and this would confirm what the books say, namely that the primary contributer to case stretch with bottle-neck cases is headspace (i.e., case set-back after obturation).
By the way, if the goal of this thread was to keep things at the "basics" level, we have failed quite miserably. Mea culpa.